Double chromosomal translocation in an infertile man: one-step FISH meiotic segregation analysis and reproductive prognosis

Abstract

Background The prevalence of chromosomal translocations is 1/500 in the general population. While in the vast majority of cases, carriers have a normal phenotype; they can present with difficulty conceiving due to the presence of a proportion of unbalanced gametes as a consequence of abnormal chromosomal segregation during meiosis. Since complex translocations involve three or more chromosomes, meiotic segregation leads to a greater number of possible combinations which effectively complicate both their study and therapeutic care. Case presentation We report on the case of a male carrier of a complex homogeneous double Robertsonian translocation: 44, XY, der(13;14)(q10;q10),der(21;22)(q10;q10). We studied his meiotic segregation by FISH on spermatozoa from the initial sample, as well as following discontinuous gradient centrifugation and after incubation in an hypo-osmotic solution. Conclusion We report a method to study in a simple single-step manner the meiotic segregation of double Robertsonian translocations in spermatozoa. Further, our results suggest that reproductive prognosis of affected individuals may be markedly improved by HOST-based sperm selection (HBSS).

Chromosomal segregation in sperm of the Robertsonian translocation (21;22) carrier and its impact on IVF outcome

“…Pierron et al [15] and our results have shown that both sperm preparation methods show a similar distribution of alternate and adjacent sperm.…”

“…So far, there were five cases of male RobT carriers t(21;22) described in the literature [6,10,[13][14][15].…”

Case report: Optical genome mapping revealed double rearrangements in a male undergoing preimplantation genetic testing

“…In the general population, balanced chromosomal rearrangements which include reciprocal translocation and Robertsonian translocation have a prevalence of about 1/500 (Pierron et al, 2019). The prevalence in male with azoospermic or severe oligozoospermia, and couples with a history of IVF failure and recurrent miscarriage reaching 1.4% and 2.2%, respectively (Clementini et al, 2005;Liu et al, 2013;Zhang et al, 2018).…”

“…Oskar A. Haas, St. Anna Children's Hospital, Austria also be called double rearrangement (Madan, 2013;Pierron et al, 2019). CCR carriers have a higher risk of unbalanced chromosomes developing in their gametes (Escudero et al, 2008).…”