ICSI and the transmission of X-autosomal translocation: a three-generation evaluation of X;20 translocation: Case report

Abstract

Published reports show that male carriers of an X-autosome translocation, which is either inherited from their mother or is de novo, are generally sterile, regardless of the position of the breakpoint in the X chromosome. We report a three-generation propagation of such a translocation in a family with a case of male factor infertility. Due to the condition of severe oligozoospermia, the proband and his wife underwent ICSI, which resulted in the birth of a normal healthy female. Cytogenetic (chromosome) analyses and X-chromosome inactivation (XCI) assays were done on the family. The cytogenetic analysis of the proband, a man with severe oligozoospermia, revealed an X-autosomal translocation, 46,Y,t(X;20)(q10;q10), which was inherited from his mother. His brother had the same translocation. Amniocentesis and post-natal umbilical cord analyses revealed that the female infant carried the same translocation as her father. XCI studies showed highly skewed inactivation of the normal X chromosome in the female infant, her paternal grandmother, and her mother who had a normal karyotype. In contrast to the data from the literature, our study suggests that men with a certain type of X-autosomal translocation could conceive children through ICSI in conditions in which a few spermatogonia are able to complete meiosis II. The literature involving X-autosomal translocation in males is also reviewed and the importance of the study of X-chromosomal inactivation in female infants discussed.

18, X, Y aneuploidies and transmission electron microscopy studies in spermatozoa from five carriers of different reciprocal translocations

“…Azoospermia is the most common finding in male carriers of an X auto somal translocation [20], as also reported recently in a reciprocal translocation t (X;11) [21]. However a few cases with severe oligozoospermia have been reported [20], including the case reported in the present study where the patient showed a severe oligoasthenotera tozoospermia and a high frequency of unbalanced chromosome complement. Translocations involving a portion of the X chromosome have a deep impact on spermatogenesis that can lead to the formation of elon gated spermatids, but the process is remarkably ineffi cient, as indicated by the presence of a small number of spermatozoa.…”

“…Translocations involving a portion of the X chromosome have a deep impact on spermatogenesis that can lead to the formation of elon gated spermatids, but the process is remarkably ineffi cient, as indicated by the presence of a small number of spermatozoa. In these cases ICSI techniques should be performed with the risk that X autosomal translocation can be transmitted to offspring as demonstrated by Ma et al [20] in a t(X;20) carrier.…”

Somatic chromosomal abnormalities in infertile men and women

“…Hitherto existing experiences with ICSI: Recently, the successful outcome of ICSI in a male carrier of an X-autosome translocation with a table of former published cases with Xautosome translocations was presented by Ma et al (2003b). They described a man with severe oligozoospermia and a maternally inherited translocation: 46,Y,t(X;20)(q10;q10).…”

X‐chromosome inactivation and telomere size in newborns resulting from intracytoplasmic sperm injection

“…A karyotype from umbilical cord blood was available for all studied cases. One of these infants was a reciprocal translocation carrier [46,X,t(X;20)] [Ma et al, 2003].…”