No abstract

Apparently healthy children living in areas where rickets is prevalent have risk factors for rickets and a small proportion will have evidence of biochemical rickets.

Recent genome-wide association studies identified single nucleotide polymorphisms (SNPs) on the chromosome 9p21.3 conferring the risk for CAD (coronary artery disease) in individuals of Caucasian ancestry. We performed a genetic association study to investigate the effect of 12 candidate SNPs within 9p21.3 locus on the risk of CAD in the Saudi population of the Eastern Province of Saudi Arabia. A total of 250 Saudi CAD patients who had experienced an myocardial infarction (MI) and 252 Saudi age-matched healthy controls were genotyped using TaqMan assay. Controls with evidenced lack of CAD provided 90% of statistical power at the type I error rate of 0.05. Five percent of the results were rechecked for quality control using Sanger sequencing, the results of which concurred with the TaqMan genotyping results. Association analysis of 12 SNPs indicated a significant difference in the genotype distribution for four SNPs between cases and controls (rs564398 p = 0.0315, χ 2 = 4.6, odds ratio (OD) = 1.5; rs4977574 p = 0.0336, χ 2 = 4.5, OD = 1.4; rs2891168 p = 1.85ˆ10´10, χ 2 = 40.6, OD = 2.1 and rs1333042 p = 5.14ˆ10´9, χ 2 = 34.1, OD = 2.2). The study identified three protective haplotypes (TAAG p = 1.00ˆ10´4; AGTA p = 0.022 and GGGCC p = 0.0175) and a risk haplotype (TGGA p = 2.86ˆ10´10) for the development of CAD. This study is in line with others that indicated that the SNPs located in the intronic region of the CDKN2B-AS1 gene are associated with CAD.

β-thalassemia is a group of heterogeneous recessive disorders common in many parts of the world. Al-Qatif and Al-Hassa oases in the Eastern Province of Saudi Arabia are regions known for high frequency of these disorders. Using two molecular methods, based on multiplexing-amplification refractory system and reverse hybridization principles, the spectrum of β-thalassemia in the region was studied. Sixty-nine subjects with known β-thalassemia disease and volunteers with high hemoglobin A2(HbA2) and low mean corpuscular volume (MCV) were included in this study. Ten mutations were detected in 91% of the subjects under study. Six of these mutations had previously been observed while the other four mutations are reported here for the first time. In addition, four of the mutations accounted for 76.8% of the subjects studied. IVSII-1 (G > A), IVSI-5 (G > A), and codon 39 (C > T) mutations were found to be the most frequent. However, the frequencies of different mutations reported here are slightly different from those reported earlier. A number of these mutations were also found in the neighboring countries, which can be explained in terms of gene flow.