Association of the CYP17 and CYP19 gene polymorphisms in women with polycystic ovary syndrome from Punjab, Pakistan.

BACKGROUND: Polycystic ovarian syndrome (PCOS) is considered the most common multifactorial endocrinopathy. Genetic factors play an essential role in the pathogenesis of PCOS. CYP 17 enzyme is responsible for androgenesis, while CYP 19 enzyme works for androgen conversion into aromatic estrogen. Several studies have reported their association with PCOS. This study was aimed to investigate the association of cytochrome P450c17α gene (CYP17) 5'-untranslated region MspA1/(rs743572) genetic polymorphism and rs2414096 of cytochrome P450 or aromatase (CYP19) gene polymorphism with the susceptibility to PCOS in reproductive-age women from Punjab, Pakistan. METHODS: We performed a case-control association study was conducted, including 204 PCOS patients and 100 controls. Genotyping of SNP rs2414096 (CYP 19 gene) and P450c17α gene (CYP17) 5'-untranslated region MspA1 was performed on genomic DNA using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Statistical analysis was performed to find out the association of phenotypic and genotypic characters in etiopathology of PCOS. RESULTS: The genotype distribution for CYP 17 5'-UTR MspA1 (TT, TC, CC) revealed that the frequency of genotype TC is significantly higher in PCOS patients (54.9%) vs. controls (OR 4.97, 95% CI 2.75-8.33, p<.001) (12%). The genotype distribution for CYP 19 (GG, GA, AA) showed significantly higher frequency of GA (58.%) and AA (23.5%) in patients as compared to cases (18% and 8%, respectively) (OR 5.49, 95% CI 3.61-8.34, p<.001). Body mass index (BMI), waist, hip, infertility and family history of infertility, PCOS, diabetes, and hypertension were found significantly associated with PCOS. CYP 19 genotypes were found significantly associated with PCOS patients having paraclinical traits of infertility and family history of infertility, while CYP 17 genotypes showed no significant association with any paraclinical traits in PCOS patients. CONCLUSIONS: This is the first study on PCOS genotypes from Pakistan and results suggest that CYP 17 5'-UTR MspA1 (rs743572) (genotype TC) and CYP 19 gene (rs2414096) (genotype GA) polymorphisms are significantly associated with susceptibility to PCOS in Pakistani women having the traits of infertility and family history of hypertension.

The combined role of allelic variants of IRS-1 and IRS-2 genes in susceptibility to type2 diabetes in the Punjabi Pakistani subjects.

BACKGROUND: Diabetes mellitus is a multifactorial disorder characterized by a high level of glucose in the blood. Both genetic and environmental factors interact to cause diabetes. Insulin receptor substrate (IRS) proteins have a significant part in insulin signaling pathways. We aimed to investigate the relationship of type 2 diabetes with a Gly972Arg (G972R) variant of the IRS-1 gene and Gly1057Asp (G1057D) polymorphism of IRS-2 gene in the population of Punjab, Pakistan. METHODS: We collected 926 samples, 500 healthy controls (fasting blood sugar < 99 mg/dL, random blood sugar < 126 mg/dL) and 426 cases with diabetes (fasting blood sugar > 99 mg/dL, random blood sugar > 126 mg/dL). Several anthropometric measurements were measured. Statistical analysis was performed by using SPSS to determine the allele group/genotype frequency of the selected variants in the study population. RESULTS: The genotyping results of G972R by RLFP-PCR showed the allelic frequency of G = 0.68 and R = 0.32 in controls while G = 0.71 and R = 0.29 in the cases. The minor R allele had a slightly higher frequency in the cases than the controls (OR = 0.86, CI 0.706-1.052, p = 0.17). The genotyping results of G1057D showed allelic frequency G = 0.74 and D = 0.26 in the controls while G = 0.961 and D = 0.29 in the cases. The minor D allele appeared to be a risk allele for this SNP although the difference in the allele frequencies was not statistically significant (OR = 1.55, CI 0.961-1.41, p = 0.108). The combined genotype analysis showed that the difference in the allele and genotype frequencies reached statistical difference between the cases and the controls as well as the odds ratio substantially increased when the R allele (G972R) was present together with D allele (G1057D) in any combination. When the association of single variants with the lipid traits was observed, only D allele (G1057D) showed significant association with TG, HDL and LDL, however when the analysis was repeated for combined genotypes using general linear model, many more significant associations between the genotype where D allele and R allele are together, were seen with many lipid traits. CONCLUSION: In conclusion, the single nucleotide polymorphisms with low-modest effect size may not affect the phenotype individually but when in combination, the effect becomes stronger and more visible, therefore, for the SNP association studies, the more the number of SNPs included in the analysis, the more meaningful the results.