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Identification of variants in exon 4 of the LDLR gene and assessment of their effects on the produced proteins in saudi women with metabolic syndrome

Diabetology & Metabolic Syndrome volume 17, Article number: 91 (2025) Cite this article

Abstract

Background

Genetic factors might influence metabolic syndrome (MetS) or any of its components. It was postulated that low density lipoprotein receptor (LDLR) gene variants could play a role in cholesterol hemostasis and the development of MetS. However, the causal-effect relationship between such variants and the development of MetS is not clearly identified or even studied before in Saudi Arabian women. This study aims to identify the variants of LDLR exon-4 in Saudi Arabian women with MetS in comparison to healthy women and to assess the expected effect of amino acids alterations on the structure and functions of the LDLR proteins.

A total of 208 female Saudi patients with MetS and 104 controls were included in the study. The exon 4 of LDLR gene was studied by DNA sequencing (Sanger) and structural analysis was performed using Project HOPE software.

Results

Four variants were identified; 2 were missense variants (2.4%; 5/208): (p.D172N and p.D178N) and 2 were nonsense variants (stop gained) (1.44%; 3/208): (p.E140* and p.L135*). Structural analysis of the expected effects of such variants revealed that they might disrupt their interactions with other proteins or biomolecules, additionally, the nonsense variants via expressing a stop codon, these will produce a truncated protein resulting in a defective function of LDL receptor.

Conclusions

Four variants in the LDLR gene, exon 4 (2 missense and 2 nonsense variants) have been identified and their expected structural effects were assessed in Saudi Arabian women with MetS in Makkah region.

Introduction

Obesity has been recognized as a major health care problem and worldwide epidemic, with more than three hundred million adults with obesity and about one billion overweighs [1, 2]. Metabolic syndrome (MetS), as metabolic disorder that is highly associated with the risk for cardiovascular disease and diabetes mellitus type 2, has become the recent epidemic of the twenty-first century [3], being associated with hypertension, increased in low density lipoproteins (LDL), central obesity, dyslipidemia, lower concentration of high-density lipoproteins (HDL), and type-2 diabetes. Morbidity and mortality attributed to increased incidence of cardiovascular disease (CVD) associated with MetS has increased significantly [4] and became the common cause of death in Western world [2]. Waist circumference the most accurate indicator of obesity constitutes a precise definition of MetS in addition to other attributes [5]. At the genetic level, it has been postulated that obesity may result from an enormous array of alterations in the LDLR gene, causing alteration of the functions of LDL receptors on the hepatocyte and consequently raising the plasma LDL levels [6, 7].

Lipoproteins play an essential role in the occurrence and progress of MetS [3], with their capability to affect plasma levels of lipid and cholesterol, the polymorphisms of LDLR gene might contribute to MetS development. This hypothesis has been tested in several populations, with inconsistent outcomes. [8, 9]. The cell-surface glycoprotein known as LDLR is in responsible for the uptake and eliminating cholesterol-rich lipoprotein particles from the circulatory system [10, 11]. The 45-kb LDLR gene, which is found on the distal short arm of chromosome 19, codes for the mature LDLR protein; a trans- membrane protein with 839 amino acids [11, 12]. The peptide's functional domains and exons line up as follows: Exon 1, the signal sequence, exons 2–4, the ligand binding domain, exons 7–14, the O-linked carbohydrate domain, exon 15, the trans membrane domain, exon 16, 41 bp of exon 17, and the cytoplasmic domain, which are the remaining portions of exons 17 and 18 [13, 14]. Exon 4 is the largest exon; nevertheless, the distribution of variants along this gene becomes more even when the number of variants per base pair is considered, suggesting that mutation could occur anywhere in the gene and could affect cholesterol hemostasis [15, 16].

Based on the functional and biochemical investigations of LDLR, genetic alterations could be categorized into 5 classes. Class 1 mutations consist of null alleles with no production of LDLR protein. Class 2 mutations produce altered LDLR proteins, which have defective capacity for being transported from the endoplasmic reticulum to the Golgi apparatus, such defects might be either complete in class 2-A or partial inhibition of the transportation of protein in class 2-B. Class 3 mutations encode LDLR proteins, which are unable to bind the ligand, LDL. Class 4 mutations produce LDLR, which inhibits the LDL internalization. Finally, class 5 mutations produce recycling defective receptors such as the missense genetic alterations in EGF precursor-like domain that produce LDLR, which are unable to release LDL in endosomes preventing the recycling of their receptors [17, 18]. Mutation screening in the global population identified more than 3000 mutations reported in LDLR gene [19], also has been evidenced from the Leiden university database (databases.lovd.nl). Mutations in LDLR gene comprise large genomic rearrangements such as insertions, deletions, as well as nonsense, missense, and frame-shift alterations. Most of population shows distinctive diversity of mutations; however, some populations might exhibit slight numbers of mutations that are predominant; as a result of a founder effect [20, 21]. Conversely, it has been previously displayed that the existence of a mutation in the LDLR does not certainly lead to disturbance in cholesterol hemostasis [22, 23]. Thus, to determine their pathogenic mechanisms, there is a requisite for functional validation of LDLR mutations [24].

Next-generation sequencing (NGS) is presently widely used for clinical applications and represents an efficient tool for the diagnosis of familial hypercholesterolemia (FH) [25]. Although the prevalent type of FH is mainly caused by LDLR small-scale pathogenic variants, these variants represent the underlying molecular abnormalities in around 10% of patients [25]. Rodríguez-Gutiérrez et al., (2024) have found in their study that large number of patients with the LDLR c.2271del mutation (99.4%) might be attributed to a founder effect and inbreeding, allowing to find both considerable biochemical variability and inadequate penetrance [26].

By NGS, Al-Allaf et al., (2015) have identified one novel variant in LDLR gene c.2026delG; p. (G676Afs*33) in Saudi Arabian population that was found in exon-14 as a novel heterozygous variant derived from a male [27]. Subsequently, they found this mutation as a recurrent frame shift mutation p.(G676Afs*33) in exon 14 of the LDLR gene [17]. Additionally, a study in the Saudi population with FH has documented that 25 mutations were found in exon-3 among patients and 2 mutations in controls, five mutations were identified within exon-4 and no mutations were detected in exon-14 among those patients [20]. Recent studies from Saudi Arabia also suggested that women with MetS are prone to serious CVD [28, 29]. To the far of our knowledge, there are no previous studies describing the association of LDLR mutations in Saudi women population with MetS. The aim of the current work was to evaluate the role of LDLR gene exon-4 mutations in the development of MetS among Saudi women, as disease risk factor based on genetic mutations in LDLR gene.

Materials and methods

Patient’s selection

The present study included 208 Saudi female patients who were fulfilling the criteria for diagnosis of MetS as being defined by using Adult Treatment Panel III (ATP III) of the National Cholesterol Education Program (NCEP) guidelines. According to five major components including: (i) Hypertriglyceridemia TG ≥ 150 mg/ dL; (ii) WC ≥ 88 cm for women; (iii) Blood pressure systolic—BP ≥ 130 mmHg; diastolic BP ≥ 85 mmHg; (iv) HDL-C < 50; and (v) FPG ≥ 110 mg/dL [30]. Any three of these five components was considered as diagnostic criteria for the metabolic syndrome [31]. In addition, the study included 104 healthy females. They included as a control group with the followed criteria (BMI ≤ 25 kg/m2, normal lipid profile, normal abdominal ultrasonography and anthropometric measures). The controls also had no previous history of CVD or family history of hyperlipidemia. All the patients and controls were from Makkah region. The patients were recruited from King Abdul Aziz hospital’s endocrinology clinic during the period from January 2019 to March 2021. The study was conducted in accordance with the principles of the Helsinki Declaration. Ethical approval for the study was given from Umm Al-Qura University Research and Ethics Committee. Written informed consent was obtained from all patients and controls under study. The age of patients and controls was between 20 and 60 years. Patients who were on hormonal medications, lipid lowering drugs, and those with severe cardiovascular diseases (CVD) like stroke and subjects who did not give consent were excluded. Using a questionnaire, information on age and disturbance of menstrual cycle were obtained. Weight, height, waist circumference, systolic and diastolic blood pressures were measured.

Sample collection

Fasting peripheral blood samples (10 mL) were collected from all participants, each sample was divided into three tubes. Serum was used for estimation of lipid profile including triglycerides (TG), total cholesterol (TC), low density lipoproteins-cholesterol (LDL-C) and high-density lipoproteins- cholesterol (LDL-C). Plasma was used for estimation of fasting blood glucose (FBG). Biochemical parameters were measured by direct homogenous method and enzymatic colorimetric tests [32], the kits were provided by HUMAN Gesellschaft für Biochemica und Diagnostic GmbH. Whole blood was used for genetic analysis.

Sequencing for exon 4 of LDLR gene:

Extraction of genomic DNA from peripheral blood leukocytes using standard protocol of Thermo Scientific Gene JET whole blood genomic DNA purification mini kit (K0781, Thermo Fisher Scientific, USA). The extracted DNA concentration was measured by Nanodrop 2000C spectrophotometer (Thermo Fisher Scientific, USA). Polymerase Chain Reaction (PCR) was performed in a total volume of 25 μL reaction mixture that contains 8.5 µl nuclease free RNA water, 12.5 µl GoTaq® G2 Green Master Mix (Promega, USA), 1 µl of each 10 µM LDLR exon 4 forward primer 5′-ATAGAATGGGCTGGTGTTGG-3′ and LDLR exon 4 reverse primer R: 5′-GAGCCCAGGGACAGGTG-3′ and 2 µl DNA (50–100) ng. The PCR was performed using, a Veriti™ Thermal Cycler, 96-well fast (Applied Biosystems, USA). The amplification thermal profile was as follows; an initial denaturation was set up for 3 min at 95 °C followed by 36 cycles of denaturation for 30 s at 95 °C, annealing for 30 s at 56 °C, extension for 30 s at 72 °C and the final extension was at 72 °C for 5 min [33]. Primers were designed by Exon Primer program (www.helmholtz-muenchen.de) and purchased from IDT (Integrated DNA Technology) for exon4 of the LDLR gene. Following the PCR amplification and characterization of the product forward and reverse, sequencing was carried out at a commercial facility (Macrogen Inc., Seoul, Korea); in which there was PCR product purification using QIAquick PCR Purification Kit (QIAGEN, USA), sequencing of the purified PCR by using BigDye terminator V3.1 Cycle Sequencing kit (Applied Biosystems, USA), and Purification of cycle sequencing products using BigDye Xtrerminator Purification kit (Applied Biosystems, USA). Sequencing was performed using 3500 Genetic Analyzer (Applied Biosystems, USA). The sequence chromatograms were displayed and checked for quality by Mutation Surveyor program version 5.2.0. (developed by SoftGenetics). Obvious changes within the examined DNA sequences were noticed through multiple sequence alignment using BioEdit [34]. Chromatograms ABI files variations were searched by Gene Screen program [35] for detection and annotation of rare sequence variants that facilitate comparison to a reference sequence and efficient identification of mutations. The NCBI Nucleotide database was searched and used for comparison and detection of variations in the LDLR gene exon 4, the wild type sequence obtained for the LDLR from NCBI Reference Sequence: NG_009060.1 [36]. The variant nucleotides were confirmed using I-mutant version 3 program [37].

All variants had been verified via the Single nucleotide variants (SNVs) annotation by variant effect predictor (VEP) from Ensembl Genome Browser; Genome Reference Consortium Human Build 37 (GRCH37) assembly https://www.ensembl.org/Homo_sapiens/Tools/VEP [38]; Expasy proteomics UniprotKB databases p01130 LDLR_Human (https://www.expasy.org/genomics/characterisation_annotation) [39] and the Human Gene Mutation Database (http://www.hgmd.cf.ac.uk/ac/index.php) [40].

Structural analysis of the identified mutations on the LDLR protein

The protein sequence of LDLR gene was downloaded from Expasy scientific database and software tool (expasy.org) [41]. The secondary structure for LDLR protein sequence was carried out by RaptorX (raptorx.uchicago.edu) [42]. Modeling the molecular effect of mutations on protein structures can significantly change the stability of protein. To investigate the stability differences between native and mutant for MetS, structural analysis of the protein modeling was performed using Swiss-model which was used to predict the tertiary model of the protein [43]. All missense mutations previously described, leading to amino acid changes in the LDLR gene protein, impact residues that are evolutionarily conserved across species. Identification of functional variants was done by predicting those which substitute the amino acids that are critical for LDLR exon 4 function. The analysis was performed using Project HOPE software to predict the effect of mutation on protein stability and characterizes the effect of amino acid substitution on protein function of the LDLR protein https://www3.cmbi.umcn.nl/hope/input/ [44].

Statistical analysis

All statistical analysis was conducted using IBM SPSS software package version16.0. Descriptive and correlation analyses were carried out, independent sample t-test and Bivariate Pearson correlation coefficient was utilized to determine the relationship between variables. P-values less than 0.05 were considered statistically significant. All results are two-tailed. Graphing was done using Graph Pad prism 7 software version 7.03 computer software.

Results

Anthropometric, clinical and laboratory parameters of the studied patients:

Two hundred and eight (208) Saudi female patients diagnosed as MetS and 104 females as controls were included in this study. Anthropometric, clinical and laboratory parameters of the studies patients and controls were shown in (Table 1). The mean age of patients and controls were 43.0 ± 9.0 years and 39.73 ± 10.41 years respectively. Components of MetS such as diabetes mellitus, hypertension, and body mass index (BMI) were measured. The BMI and WC were significantly higher among patients (BMI ≥ 30 kg/m2) in comparison to controls (BMI ≤ 25 kg/m2) (p. = < 0.01 for both). Also, the mean diastolic blood pressure and FBG were significantly higher among patients than controls (p = < 0.01 for both). The lipid profile including triglycerides, total cholesterol, LDL and HDL were significantly higher among patients than among controls (p = < 0.001 for all lipid profile).

Table 1 Anthropometric, Clinical and laboratory parameters of the Saudi Arabian Women with Metabolic Syndrome
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LDLR exon 4 gene variants:

The product size of LDLR gene exon 4 was 501bp (Fig. 1). By using Sanger DNA sequencing, different variants in LDLR gene exon 4 were identified in 8 of female patients with MetS (3.85%; 8/208). No variants were detected in the remaining 200 (96.15%; 200/208) patients. The 104 control subjects did not show any variants in exon 4 of the LDLR gene. SNVs such as missense and nonsense variants were detected in exon 4 of the LDLR gene; these variants were summarized in (Table 2). Four variants were identified in this study; two were missense variants; c.514G > A, p.D172N (rs879254554) and c.532G > A, p.D178N (rs879254565); and 2 were nonsense variants (stop gained), c.418G > T, p.E140* (rs748944640) and c.404T > A, p.L135*. There was heterozygous transition (G > A) in the missense variants p.D172N and p.D178N; while there was heterozygous transversion in both nonsense variants p.E140* (G > T) and p.L135* (T > A). According to The American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG-AMP) standards and guidelines[45], the variants in this study were classified into; pathogenic variants as in p.E140* and p.L135*; likely pathogenic variant as in p.D178N; pathogenic/ likely pathogenic variant as in p.D172N. The previous variants were associated mainly with atherosclerosis and FH. Both nonsense variants p.E140* (G > T) and p.L135* (T > A) express a premature stop codon at position 140 and 135 respectively. The Electropherograms of mutant and wild type for each variant were shown in (Figs. 2, 3, 4, 5).

Fig. 1
figure 1

LDLR gene Exon 4 product size (501 bp)

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Table 2 LDLR exon 4 gene variants identified by Sanger Sequencing and their frequency in the study
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Fig. 2
figure 2

Electropherograms showing LDLR gene exon 4 variants: c.418G > T, p.E140*, ACGAG > ACKAG (Nonsense variant); K is a DNA letter code; K = G or T (Heterozygous transversion)

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Fig. 3
figure 3

Electropherograms showing LDLR gene exon 4 variants: c.514G > A, p.D172N, CCGAC > CCRAC (Missense variant); R is a DNA letter code; R = G or A (Heterozygous transition)

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Fig. 4
figure 4

Electropherograms showing LDLR gene exon 4 variants: c.532G > A, p.D178N, CGGAT > CGRAT (Missense variant); R is a DNA letter code; R = G or A (Heterozygous transition)

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Fig. 5
figure 5

Electropherograms showing LDLR gene exon 4 variants: c.404 T > A, p.L135*, CTTGG > CTWGG (Nonsense variant); W is a DNA letter code; W = T or A (Heterozygous transversion)

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The impact of the LDLR variants on the structure and function of the LDLR protein

The original wild-type residue and newly introduced mutant residue exhibit contrasting properties. The mutated residue adds an amino acid with distinct characteristics, which can disturb this domain and eliminate its function. The wild-type and mutant amino acids exhibit differences in size, charge, and hydrophobicity-value which may result in a possible loss of external interactions. The mutant residue is situated in a domain that is crucial for binding of other molecules and in direct contact with residues in a domain that is also significant for binding. The mutation could potentially disrupt the interaction between these two domains and hence impacting the protein’s function. Based on the finding from Project hope mutation analysis, the variants identified in the present study were evaluated for their effect on contacts made by the mutated residue and structural domains in which the residue was located. The impact of the LDLR variants on the structure and function of the LDLR protein was demonstrated in (Table 3, Fig. 6).

Table 3 Project hope mutation (1|P01130|LDLR_HUMAN) to predict the effect of the LDLR mutations on the structure and function of the LDLR protein (Venselaar et al., 2010)
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Fig. 6
figure 6

The protein structure of LDLR-exon4, highlighting variant positions and comparing them to the reference amino acids: 6(a): p.D172N; and 6 (b): p.178N

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In p.D172N, the mutated residue is located near a residue that produces a cysteine bond. This cysteine bond itself is unaltered but could be influenced by the nearby mutation. The wild-type residue charge in p.D172N and p.D178N, was negative, while the mutant residue charge is neutral. Due to the loss of negative charge, the interaction with the metal will become less stable, which can disrupt the domain. This mutation results in the loss of the charge of the buried wild-type residue. The residue at position p.D172N is not conserved in the wild type. Different residue types were observed more often at this position in other homologous sequences. Mutant residue was also found on this position. According to the conservation information the mutation is likely not damaging the protein. In p.D178N, the wild-type residue is well conserved, while a few alternative residue types have been detected at this position. No mutant residue or any other residue type with similar properties was detected at this position in other homologous sequences. According on conservation information this mutation is likely to cause damage to the protein. In both nonsense variants p.E140* and p.L135*, a truncated LDLR protein is produced, which is either degraded affecting LDLR protein levels or it might alter the normal assembly of the protein complex causing a defective function of LDL receptor.

Discussion

In this cross-sectional study, genetic variations of LDLR gene, exon-4 had been investigated in female patients with MetS in comparison to healthy women. To the far of our knowledge, this might be the first study to identify these variations in Saudi women with MetS and to investigate the expected effects of these mutations on protein stability and characterize the consequence of the substitution of these amino acid on the functions of the LDLR proteins. The association of obesity with dyslipidemia and MetS was well established; however, the causal-effect relationship of LDLR gene mutations on MetS is not clearly understood. Previous studies have shown heterogeneity of LDLR gene mutations responsible for FH but not for MetS and there was a broad spectrum of mutations within LDLR gene which has been frequently associated with hypercholesterolemia [46, 47]. FH is underdiagnosed in the Middle East [48]. Atoum et al., (2011) studied the variations and the genetic polymorphism in exon-4 of LDLR amongst Jordanian patients with FH, their study showed a wide spectrum of polymorphism in exon-4 among them [49].

In this study, the molecular variations in 208 women with obesity having MetS criteria attending outpatient clinic at King Abdul Aziz hospital and matched 104 healthy controls using capillary sequencing method for the LDLR exon-4 were screened. Out of 208 women with MetS; 27 cases have SNVs that include missense and nonsense variants. In another study from Saudi Arabia women with MetS and polycystic ovarian syndrome have shown increased risk of CVD [50]. Also, several studies from Saudi Arabia and other countries have shown prevalence of compound heterozygous and homozygous mutations in LDLR gene in patients with FH [51, 52]. Similarly, an earlier study was conducted by Alharbi et al., (2015) reported significant differences in the exon-4 of the LDLR gene among Saudi population with FH [20].

Three variants previously reported to be associated with FH among other populations were identified in MetS patients in the present study. In the nonsense variant (stop gained) c.418G > T; p.E140* (rs748944640), also known as FH Venezuela or FH Campobasso. p.E140* was described as the mutation that is mainly involved in the connection between the structure; function of the receptor and the clinical manifestations of FH [53]. The missense variant, c.514G > A; p.D172N (rs879254554) had been identified in heterozygous FH patients in Danish, Norwegian, Spanish, Taiwanese, and Chinese populations [54,55,56]. The missense variant c.532G > A; p.D178N (rs879254565) was identified in few studies in heterozygous FH patients and considered as likely pathogenic in Austrian and Spanish populations [57, 58]. In this study, there was rarity of the nonsense variant p.L135*, as it was identified in one patient only.

Few studies identified genetics variants related to dyslipidemia including LDLR gene as a risk factor for MetS. In the same context of our study, Lee et al., 2022, had identified genetic variants related to MetS by NGS. They identified variants in LDLR gene such as: missense variant c.769C > T; p.R257W (rs200990725), c.1765G > A; p.D589N (rs201971888) and a novel nonsense variant c.2541C > A; p. Y847* [59].

In Saudi populations, twenty-one variants in three candidate genes were found to be related to FH, most of these variants (about 80%) were in the LDLR gene, other variants were in the Proprotein convertase subtilisin/kexin type 9 (PCSK9) gene; the next major gene that is linked to FH-related mutation. The least frequent variants associated with FH were found in Apo-lipoprotein B (APOB) gene. Those genes provides several regulatory mechanisms for blood cholesterol levels [60].

Based on Project HOPE reports, several differences are shown in the secondary and tertiary structures of wild and mutant type proteins, the shapes and ionic interaction also changed in the tertiary protein structures. These changes may affect protein functions and folds. The affection of substitutions, insertions, and deletions of sequences contribute to the structural and functional diversity of proteins relatively defined in model proteins. The mutant residues were found to be completely different from wild type residues; in 3D-structure wild type residues were implicated in a metal-ion contact, thus, the different dimensions of the wild and mutant residues disrupt such interactions with the metal-ion. There are differences in charge and size between residues that can disturb the domains and abolish their functions, the mutant variants make the new residues are not in the appropriate position for formation the exact hydrogen bond as the original wild. The different hydrophobic interaction will affect hydrogen bond formation [61].

The present study might suggest that the variants of exon 4 in the LDLR gene that have been found exclusively only in MetS’ patients but not in healthy women could be a potential predictor for the development of MetS or the occurrence of its complications. Previous reports have suggested that individuals with MetS involve a broad array of CVD risk levels [62].

Conclusions

The present study showed variants of the LDLR gene exon 4 which were identified only in female patients of MetS in Makkah region (KSA) but not in healthy control women. The Saudi women with MetS exhibited the heterogeneity of variants in LDLR gene; the reason for this variation could be explained in terms of racial and ethnic heterogeneity in the population in the western region of KSA, mainly in Makkah city (Arab, Afro-Arabs and Asians). We have detected 4 variants in exon 4. The detection of these variants is important as it may be recommended to design future studies for large scale population screening programs to facilitate both the primary and the secondary preventive measures of cardiovascular disease within the region.

Availability of data and materials

No datasets were generated or analysed during the current study.

Abbreviations

A:

Adenine

AA:

Amino acid

ABI:

Application binary interface

BMI:

Body mass index

C:

Cytosine

DNA:

Deoxyribonucleic acid

EDTA:

Ethylenediaminetetraacetic acid

FBG:

Blood fasting glucose

G:

Guanine

HDL-C:

High density lipoprotein receptor

KSA:

Kingdom of Saudi Arabia

LDLR:

Low density lipoprotein receptor

LDL-C:

Low density lipoprotein cholesterol

MetS:

Metabolic syndrome

NCBI:

National center for biotechnology information

NCEP ATP III:

National Cholesterol Education Program’s Adult Treatment Panel III

PCR:

Polymerase chain reaction

RefSeq:

Reference sequence

RNA:

Ribonucleic acid

SNV:

Single nucleotide variant

TG:

Triglycerides

TC:

Total cholesterol

VEP:

Variant effect predictor

WC:

Waist circumference

SNV:

Single nucleotide variant

FH:

Familial hypercholesterolemia

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Acknowledgements

The authors would like to express their sincere appreciation to the staff of The Deanship of Scientific Research (DSR) Umm-Al-Qura University, Makkah, and to Dr. Mohamed Ahmed Salih (Department of Bioinformatics, Africa City of Technology, Sudan University of Medical Science and Technology) for the support during this study

Funding

This study was supported by a grant from The Deanship of Scientific Research (DSR) Umm-Al-Qura University, Makkah to Dr. Sameer H. Fatani (Code number- 4340109635).

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Authors and Affiliations

  1. Department of Biochemistry, Faculty of Medicine, Umm ALQura University, 21955, Makka, Saudi Arabia

    Hiba S. Al-Amodi, Sameer H. Fatani & Hala F. M. Kamel

  2. Department of Medical Biochemistry, Faculty of Medicine, National University Khartoum, Khartoum, 11115, Sudan

    Nazik Altayeb Abdelbasit

  3. Science and Technology Unit and the Department of Medical Genetics, Umm Al-Qura University, 21955, Makkah, Saudi Arabia

    Mohiuddin M. Taher

  4. Institute of Endemic Diseases, University of Khartoum, Medical Campus, Khartoum, Khartoum, 11115, Sudan

    Maowia Mohamed Mukhtar

  5. Molecular Biologist, Children Cancer Hospital Egypt, Cairo, 57357, Egypt

    Ayman S. Mohamed

  6. Clinical Pathology Department, National Cancer Institute, Cairo University, Cairo, 11796, Egypt

    Abdallah M. Gameel

  7. Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Ain Shams University, Cairo, Egypt

    Hala F. M. Kamel

  8. Clinical Biochemistry and Molecular Diagnostics Department, National Liver Institute, Menoufia University, Menoufia, Egypt

    Shimaa Abdelsattar

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  1. Hiba S. Al-Amodi
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Contributions

N.A.A; H.F.M.K; H.S.A; M.M.M; M.M.T and S.H.F responsible for conceptualization. NAA; M.M.M; M.M.T and S.H.F recruited the patients. N.A.A; A.M.G; M.M.M; M.M.T and S.H.F perform the methodology. N.A.A and A.M.G; S.A; H.F.M.K; M.M.T and A.M.G interpret the results. N.AA; S.A; H.S.A; H.F.M.K; S.H.F; M.M.M; A.M.G and M.M.T..; Wrote, reviewed and editing the manuscript. All authors have read and agreed to the published version of the manuscript and agree to be accountable for the content of the work.

Corresponding author

Correspondence to Shimaa Abdelsattar.

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Ethics approval and consent to participate

The World Medical Association’s guidelines for medical research involving human subjects (“Declaration of Helsinki”) were followed in carrying out this study. This study was approved by the ethical committee (IRB) of Umm Al-Qura University, Makkah. Written informed consent for participation in the study was obtained from all participants.

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The authors declare no competing interests.

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Al-Amodi, H.S., Abdelbasit, N.A., Fatani, S.H. et al. Identification of variants in exon 4 of the LDLR gene and assessment of their effects on the produced proteins in saudi women with metabolic syndrome. Diabetol Metab Syndr 17, 91 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s13098-025-01650-7

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Keywords

Diabetology & Metabolic Syndrome

ISSN: 1758-5996

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