Do morphological anomalies reflect chromosomal aneuploidies?

Abstract

In cases of severe teratozoospermia, the current morphological criteria used to assess chromosomal status is insufficient for the selection of spermatozoa for intracytoplasmic sperm injection (ICSI). Case histories are reported of four patients presenting 100% teratozoospermia, and the integrity of their individual chromosomal statuses is determined using a three-colour fluorescence in-situ hybridization (FISH) technique. Patient 1 presented shortened flagella syndrome, patient 2 globozoospermia, patient 3 spermatozoa with irregular acrosomes, and patient 4 macrocephalic spermatozoa with associated multiple flagella. Three-colour FISH analysis using chromosome X, Y and 1 -specific probes showed that ~95% of the spermatozoa analysed from patients 1, 2 and 3 presented X,1 and Y,1 signals, X,Y ratios and aneuploidy/diploidy rates comparable with those observed in normal controls. In contrast, patient 4 showed a highly elevated Y to X sex ratio and a highly elevated aneuploidy/diploidy rate. Three-colour FISH analysis thus demonstrates an increased incidence of chromosomal abnormalities in association with macrocephalic spermatozoa. Moreover, the analysis shows that in patients affected with either globozoospermia, shortened flagella syndrome or a condition of abnormal acrosomal spermatozoa, no association exists between chromosomal status and phenotype. Since these patients display normal haploid, sex chromosome and aneuploidy status, ICSI can be conceivably offered as a treatment for their infertility.