This study presents a 28-year-old infertile male who was referred to the cytogenetic laboratory for chromosomal analysis after 4 years of regular unprotected intercourse in whom non-obstructive azoospermia was revealed. Standard cytogenetic G-banding was performed on metaphase spreads and a de-novo karyotype 46,X,der(Y)(q11.22;p11.3) was identified. This analysis was followed by flourescence in-situ hybridization(FISH) and array comparative genomic hybridization (aCGH). Finally, the patient's karyotype was identified as 46,X,der(Y)(qter→q11.221::p11.31→qter).ish der(Y) (qter+,pter-,SHOX+,SRY+,Ycen+,DYZ3+;DYZ1+,qter+).arrYq11.221q12(14,448,863-59,288,511) x2, Yp11.32p11.31(104,062-266,388) x0. It is proposed that de-novo derivative monocentric Y chromosome with duplicated region Y qter→q11.221::p11.31→qter with partial deletion of Yp PAR1 region most probably can perturb the conjugation of sex chromosomes during first meiotic division of spermatogenic arrested differentiation (development).
