Browsing by Author "Tayeb, Mohammed T"

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    Genetic biomarkers predict susceptibility to autism spectrum disorder through interactive models of inheritance in a Saudi community
    (TAYLOR & FRANCIS AS, 05/03/2019) Bogari, Neda; Dannoun, Anas; Elhawary, Ezzeldin N; Khogeer, Asim; Arab, Arwa H.; Mufti, Ahmad; Rashad, Mona; Qutub, Nermeen; Sindi, Ikhlas A; Tayeb, Mohammed T; Elhawary, Nasser A.
    Objective: To determine whether individual or interactive single nucleotide polymorphisms (SNPs) may influence the development of autism spectrum disorder (ASD). Methods: DNA from buccal cells of 212 participants (110 cases and 102 controls) were subjected to TaqMan genotyping of the HTR2A rs7997012, HTR2C rs6318, SLC6A4 rs3813034, ANKK1 rs1800497, and BDNF rs6265 SNPs. The ASD symptoms and severity were assessed by DSM-IV criteria and CARS scores. The SNPStats software was used to determine the best interactive model of inheritance of genotypic data. Results: We found susceptibility in ASD cases when compared with controls in rs7997012 (log-additive), rs6318, and rs3813034 (overdominant) and in 1800497 and rs6265 (recessive) (P < 0.05). Heterozygosity significantly contributed to the risk of ASD for rs6318 and rs3813034 SNPs (56%, P = 0.03 and 89%, P = 0.005, respectively). The rs6318 and rs6265 SNPs were significantly associated with cases with CARS scores >= 37 (recessive) (P = 0.03 and P = 0.05, respectively). Both the rs7997012 and rs6265A variant alleles were strongly associated with ASD cases with CARS scores >= 37 (P = 0.005 and P = 0.003). Conclusions: Our study provides clear evidence of associations between all five examined biomarkers and risk for ASD. Achieving exome analyses for Saudi patients with ASD could enable to identify more genetic variants and candidate genes.
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    Risk of Colorectal Carcinoma May Predispose to the Genetic Variants of the GST, CYP450, and TP53 Genes Among Nonsmokers in the Saudi Community
    (DOVE MEDICAL PRESS LTD, 2021-04) Sindi, Ikhlas A; Babalghith, Ahmed O; Tayeb, Mohammed T; Mufti, Ahmad H; Naffadi, Hind; Ekram, Samar N; Elhawary, Ezzeldin N; Alenezi, Munaifah; Elhawary, Nasser A
    Purpose: Colorectal carcinoma (CRC) represents a considerable public health burden in Saudi Arabia. Several candidate genes and genetic variants have been associated with morbidity and mortality among patients with CRC. We explored whether allelic variants of the GSM1, GSTT1, CYP450 (rs4646903 and rs1048943), and TP53 (rs1042522) genes predisposed nonsmoking Saudi individuals to increased risk for CRC. Patients and Methods: DNA from buccal cells of 158 participants (80 with CRC and 78 healthy controls) were analyzed for five SNPs using conventional PCR and TaqMan genotyping assays. The SNPStats software was utilized to choose the best interactive inheritance mode for selected SNPs (https://www.snpstats.net). Results: The mean age of diagnosis was 62.4 +/- 13.5 years (range, 40-83 years), with those aged 71-80 years and those aged 40-50 years accounting for the most diagnoses (35.7% and 28.6% of diagnosis, respectively). The GSTM1 and TP53 rs1042522 SNPs were associated with CRC (OR= 3.7; P< 0.0001, and OR= 1.6; P= 0.033, respectively). A plausible contribution to CRC was observed for the GSTM1 and TP53 rs1042522 SNPs (x(Yates)(2)= 14.7; P= 0.00013, and x(Yates)(2)= 11.2; P= 0.0008, respectively), while the GSTT1 null variant did not affect risk. Heterozygosity in the CYP450 (rs4646903 and rs1048943 SNPs) was associated with a significant risk for CRC. The GSTM1/GSTT1 and CYP450 rs4646903/rs1048943 SNP pairs were in linkage disequilibrium, and the associations were statistically significant (P= 0.01 and P= 4.6x10(-7), respectively). Conclusion: The GSM1 and TP53 rs1042522 variants can increase the development of CRC in Saudi nonsmokers. Even the presence of one copy of a variant allele in the CYP1A1 gene can predispose CRC risk. Additional studies should also examine other SNP combinations with lifestyle factors that may help prevent, rather than facilitate, colorectal tumorigenesis