Articles written in Journal of Genetics

• Association of ADAM33 gene polymorphisms with adult-onset asthma and its severity in an Indian adult population

ADAM33, a member of the ADAM (a disintegrin and metalloprotease) gene family, is an asthma susceptibility gene originally identified by positional cloning. In the present study, we investigated the possible association of five single-nucleotide polymorphisms (SNPs) in the ADAM33 (rs511898, rs528557, rs44707, rs597980 and rs2787094) with adult-onset asthma in an Indian population. The study included 175 patients with mild intermittent ($n = 44$), mild persistent ($n = 108$) or moderate persistent ($n = 23$) subgroups of asthma, and 253 nonasthmatic control individuals. SNPs were genotyped with the help of restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) method, and data were analysed using chi-square test and logistic regression model. Bonferroni’s correction for multiple comparisons was applied for each hypothesis. Genotypes and allele frequencies of SNPs rs511898 and rs528557 were significantly associated with adult-onset asthma ($P = 0.010-\lt 0.001$). A significant association of the homozygous mutant genotype and mutant alleles of SNPs rs2787094, rs44707 and rs597980 with the asthma was also observed ($P = 0.020-\lt 0.001$). A positive association between asthma and haplotypes AGCCT, GGCCT, AGACT, GCAGT, GGACT, ACCCC and AGACC were also found ($P = 0.036-\lt 0.001$, OR $= 2.07-8.49$). Haplotypes AGCGT, GCAGC, ACAGC, ACAGT, GGAGC and GGCGT appear to protect against asthma ($P = 0.013-\lt 0.0001$, OR $= 0.34-0.10$). Our data suggest that ADAM33 gene polymorphisms serve as genetic risk factors for asthma in Indian adult population.

• Further evidence for the genetic basis of qualitative traits and their linkage relationships in dolichos bean (Lablab purpureus L.)

An investigation on inheritance of qualitative traits in dolichos bean revealed biallelic monogenic control of photoperiod-induced sensitivity to flowering time and flower colour in F$_{2}$ and F$_{3}$ generations. While, growth habit and pod curvature areeach controlled by two genes that exhibit classical complementary epistasis, raceme emergence was controlled by two genesthat displayed classical inhibitory epistasis. The dominant alleles, at two different unlinked pairs of genes are necessary forplants to exhibit indeterminate growth habit and bear straight pods. Any other combination of alleles at the two pairs of genesresult in plants displaying determinate growth habit and bearing curved pods. While, the genes controlling growth habit, PSFTand raceme emergence are linked. Those controlling flower colour and pod curvature are segregated independent of eachother. These results are discussed in relation to strategies for breeding dolichos bean.

• Prevalence of Y chromosome microdeletion in north Indian infertile males with spermatogenesis defect

Deletion of specific genes present in the long arm of Y chromosome has been identified as the most common genetic cause of defective spermatogenesis. Studies have shown that frequency of Y chromosome microdeletion varies in different geographical location and is related to genetic and environmental influence preponderance. Therefore, the present study was carried out to identify the frequency of Y chromosome microdeletion in the northern region of India and to define subgroup of infertile patients who are critically under more risk of having microdeletion. A total of 292 north Indian infertile males with nonobstructive azoospermia and oligozoospermia were selected for screening the Y chromosome microdeletion. Healthy fertile males (n=100) were also enrolled as control subjects. Frequency of Y chromosome microdeletion in north Indian infertile males was found to be about 8.5%, with azoospermia factor (AZFc) region as the most susceptible region for microdeletion. Comparatively microdeletion is more common in patients with nonobstructive azoospermia thanoligozoospermia (9.2% versus 7.1%). Statistical analysis also revealed that patients with hormonal FSH level between 20 and 40 mIU/mL have more chances of harbouring microdeletion. Hence, the present study highlights the importance of screening AZFc region among infertile patients with very high serum FSH value.

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019