Frequency of rs731236 (Taql), rs2228570 (Fok1) of Vitamin-D Receptor (VDR) gene in Emirati healthy population

© 2015 The Authors. Published by Elsevier B.V.. Vitamin D is getting more attention everyday due to its importance in maintaining bone and calcium homeostasis, cellular proliferation, differentiation and immune response. Vitamin D is derived from diet or elicited in the skin by the activation of 7-dehydrocholesterol, which is an inert molecule that must be activated by ultraviolet light to form pre-vitamin D3. Recent studies connected the gene encoding for vitamin D (VDR) to the genetic control of bone mass and other diseases. As VDR SNPs have been associated with several disorders and diseases, it\u27s important to investigate the allelic and genotypic distribution among populations. The aim of this study is to determine the frequency of rs731236 (Taq1) and rs2228570 (Fok1) variants in healthy Emirati individuals and compare their genotype and allele distribution with other populations. In this study 282 (female, 187; male, 95) unrelated healthy UAE nationals were involved. Two hundreds and eight two DNA samples been collected to genotype rs731236 (Taq1) and rs2228570 (Fok1) VDR SNPs. Our results indicate that the distribution of the alleles and genotypes of rs731236 (Taq1) and rs2228570 (Fok1) vary considerably in different populations. In the Emirati population the distribution of rs731236 (Taq1) and rs2228570 (Fok1) were AA 38%, AG 42%, GG 20% and AA 27%, AG 42%, GG 31% respectively. The Emirati population genotype and allele distribution of rs731236 (Taq1) and rs2228570 (Fok1) had no difference with Caucasians from USA and France. However, there was significant difference with Asian populations

Autosomal Short Tandem Repeat (STR) Variation Based on 15 Loci in a Population from the Central Region (Riyadh Province) of Saudi Arabia

INTRODUCTION: The small size of Short Tandem Repeats (STRs), their ubiquitous genome-wide distribution and polymorphic nature enhances their value in human forensic/population genetics applications. OBJECTIVES: This study aims to investigate the short tandem repeat variation based on 15 loci in a population from the central region of Saudi Arabia. METHODS: Allele frequency variation for 15 Short Tandem Repeat (STR) loci was examined in 190 unrelated Saudi volunteers. Results: This study summarizes the allele distribution in the Saudi population and compares them to other populations located in Asia, Africa, the Middle East and Europe. The standard forensic parameters of Observed Hetrozygosity (Ho), Expected Heterozygosity (He) and Gene Diversity Index (GD) were determined for the following 15 STR loci: D8S1179, D21S1, D7S820, CSF1PO, D3S1358, TH0, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S5, D5S818 and FGA. The most frequent alleles in the Saudi population were: 8 repeats (0.558) at TPOX, 12 (0.411) at D13S317, 12 (0.385) at CSF1PO, 11 (0.382) at D16D539 and 10 (0.358) at D7S820. The 15 markers utilized in this study are highly informative as evidenced by their high power of discrimination (PD) values with D2S1338, D19S433 and FGA having the highest PD values. The relationship between the Saudi population and other geographically distributed populations, assessed by a Multidimensional Scaling (MDS) plot, showed that the Saudi population clustered with groups from Yemen, Iraq, Qatar, Oman and Bahrain. CONCLUSION: TPOX, D13S317, CSF1PO, D16D539 and D7S820 markers were found suitable for forensic analysis, paternity testing and can also be used for chimerism study after allogenic bone marrow transplantation for Saudi population. On the other hand, the population admixture with other ethnic origins might explain the variable degree of genetic distances of this population and other Arab-related groups

Munc18-2 deficiency causes familial hemophagocytic lymphohistiocytosis type 5 and impairs cytotoxic granule exocytosis in patient NK cells

Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically heterogeneous autosomal recessive immune disorder characterized by the occurrence of uncontrolled activation of lymphocytes and macrophages infiltrating multiple organs. Disease-causing mutations in the perforin (PRF1; also known as FHL2), Munc13-4 (UNC13D; also known as FHL3), and syntaxin-11 (STX11; also known as FHL4) genes have been identified in individuals with FHL. These genes all encode proteins involved in the cytotoxic activity of lymphocytes. Here, we show that the gene encoding syntaxin-binding protein 2 (Munc18-2; official gene symbol STXBP2) is mutated in another subset of patients with FHL (designated by us as “FHL5”). Lymphoblasts isolated from these patients had strongly decreased STXBP2 protein expression, and NK cells exhibited impaired cytotoxic granule exocytosis, a defect that could be overcome by ectopic expression of wild-type STXBP2. Furthermore, we provide evidence that syntaxin-11 is the main partner of STXBP2 in lymphocytes, as its expression required the presence of STXBP2. Our work shows that STXBP2 deficiency causes FHL5. These data indicate that STXBP2 is required at a late step of the secretory pathway for the release of cytotoxic granules by binding syntaxin 11, another component of the intracellular membrane fusion machinery