Chromosomal Heteromorphisms and Primary Male Subfertility: A Case–Control Cytogenetic Study from South India

Chromosomal heteromorphic variants are usually regarded as benign; nevertheless, some studies have found an association with subfertility, and their clinical importance is still uncertain. The present case–control study was carried out in order to assess the link between chromosomal heteromorphisms and male subfertility in a South Indian population. A total of 1,200 South Indian men were included in the study, comprising 600 subfertile men who had been referred for chromosomal analysis and 600 fertile men who served as controls. For the chromosomal assessment, standard cytogenetic methods were used, such as culturing peripheral blood lymphocytes, G-banding, and karyotyping. The results indicated that the frequency of chromosomal heteromorphisms was significantly greater in the group of subfertile men than in the control group (18.3% versus 7.5%), with a statistically significant association (OR = 2.77, 95% CI: 1.92–3.99; p < 0.001). Of the variants, Yqh− and 9qh+ were found to have statistically significant associations with male subfertility, while inv (9) showed increased odds although this was not statistically significant. The findings thus suggest a possible association between chromosomal heteromorphic variants, especially those involving chromosomes Y and 9, and male subfertility.