Ring chromosome 12 and severe oligospermia: a case report

Abstract

Objective-To describe an unusual presentation of ring chromosome 12, which manifested as severe azoospermia, resulting in male infertility. Design-Case report.Setting-In vitro fertilization center at a tertiary care hospital. Patient(s)-A 27-year-old man diagnosed with unexplained azoospermia and ring chromosome 12 abnormality during a workup for primary infertility. Intervention(s)-In vitro fertilization with preimplantation genetic diagnosis.Main Outcome Measure(s)-To confirm the importance of obtaining karyotypes in individuals with severe oligospermia.Result(s)-Full-term pregnancy after IVF using donor sperm.

Azoospermia and ring chromosome 9—a case report

“…In total 84 % of cells contained the r(9) in the present case, which corresponds well with previous reports on r (12,15,21,22), in which 85-97 % of the autosomal ring chromosomes were found in relation to azoospermia [8,[20][21][22][23]. In contrast, some previous cases including fertile men with a lower degree of mosaicism (<50 %) have been described [24,25].…”

“…Moreover, the literature is sparse regarding phenotypic details and sperm status. However azoospermia has previously been reported in males with other ring chromosomes, affecting chromosomes 12, 15, 21 and 22 [4,8,9].…”

Chromosomal abnormalities and Y chromosome microdeletions in infertile men with azoospermia and oligozoospermia in Eastern China

“…Ring chromosome 12 is a rare structural chromosome abnormality. 25 One patient in our study had the karyotype 46,XY,r(12)(p13q24.3). Ring chromosomes can result from breakage of an end segment of both arms of a chromosome and subsequent end joining.…”

Sperm chromosome analysis of an infertile patient with a 95% mosaic r(21) karyotype and normal phenotype

“…When inherited, transmission frequently involves the mother (1), and in that particular case, parenthood is possible. But in the man, it is frequently associated with severe failure of spermatogenesis leading to azoospermia, cryptozoospermia, or oligospermia (5)(6)(7). Meiotic studies of an azoospermic male with r(21) indicated a failure of chromosome 21 pairing and a spermatogenesis arrest during the first meiotic division (8).…”