Homozygosity and Heterozygosity of the Pericentric Inversion of Chromosome 9 and Its Clinical Impact

Abstract

Introduction: This paper presents a detailed study of inversion in chromosome 9 and its correlation with sub-fertility amongst 26 couples. Until now, there have been conflicting views on the clinical outcome of the pericentric inversion in chromosome 9. Many researchers consider this anomaly as a predisposing factor for infertility. Methods: In the present study, the karyotyping analysis of 500 couples was carried out to investigate the genetic basis for infertility in these subjects. Results and Conclusion: It was observed that a significant fraction (5.2%) of the total group had a pericentric inversion in chromosome 9 as the only known abnormality. The incidence of this abnormality in infertile patients was significantly higher than the reported value of 1%-3% in the normal population. Moreover, it was observed that the incidence of the inv (9) karyotype in the male patients was 2.5 times higher than that in females. These correlations clearly indicated that the inv (9) karyotype was not a normal karyotype but that it had a harmful effect on fertility.