VDR (Apa 1) Gene Polymorphism in Asthma in Karachi Population

Background:
Asthma, a chronic allergic respiratory disease, is influenced by complex gene environment interactions. Variations in the vitamin D receptor (VDR) gene have been linked to asthma susceptibility and severity. This study aimed to determine the distribution of VDR (ApaI) gene polymorphisms among asthmatic patients in Karachi.
Method:
A total of 146 asthmatic patients were recruited from the outpatient unit of Ziauddin Hospital, Karachi, after obtaining informed consent. Genomic DNA was extracted from blood samples and subjected to polymerase chain reaction followed by restriction fragment length polymorphism (RFLP) analysis to identify ApaI genotypes (AA, Aa, aa). Data were analyzed using SPSS Version 24. Quantitative variables were expressed as mean ± SD, and qualitative variables as frequencies and percentages. Associations between genotypes and demographic factors (age group, gender) were evaluated using the Chi-square or Fisher’s exact test, with p ≤ 0.05 considered statistically significant.
Results:
Participants ranged in age from 10 to 77 years, with a mean of 42.79 ± 15.62 years. The majority of patients were within the 21–40 (39.7%) and 41–60 (39.0%) age groups. Males comprised 58.9% and females 41.1% of the study population. The most frequent genotype was aa (45.2%), followed by AA (34.2%) and Aa (20.6%). No statistically significant association was found between VDR (ApaI) genotypes and demographic characteristics.
Conclusion:
The aa genotype of the VDR (ApaI) polymorphism was predominant among asthmatic patients in Karachi. However, no significant association was observed between VDR genotypes and demographic variables.

Asthma, vitamin D3, polymorphism, genetic association, Pakistani population.