Molecular and Clinical Characteristics of 26 Cases with Structural Y Chromosome Aberrations

Abstract

Structural abnormalities include various types of translocations, inversions, deletions, duplications and isochromosomes. Structural abnormalities of the Y chromosome are estimated to affect less than 1% of the newborn male population and are particularly hazardous for male reproductive function. The objective of this study was to characterize a group of patients with structural abnormalities of the Y chromosome. All patients who visited our laboratory between 2007 and 2010 underwent cytogenetic investigations. Among these, we detected 26 patients with structural abnormalities of the Y chromosome. To confirm the structural Y chromosome alterations, we used special bandings, FISH and multiplex PCR to detect Y chromosome microdeletions. Of the 26 patients presented here, 11 had an isodicentric Y chromosome, 7 had an inversion, 3 had a translocation, 2 had a derivative, 2 had a Yqs and 1 had a deletion. Sixteen were diagnosed with azoospermia, 8 as normal fertile males and 1 as a man who was unable to donate semen due to mental retardation. One of the patients having 45,X/46,X,idic(Y) was reported to be phenotypically female with primary amenorrhea and without uterus. Deletions of the AZFbc region were correlated with the sperm concentration (p < 0.05), but no correlation with the levels of FSH, LH, testosterone, prolactin and estradiol were found. The present report shows that the precise identification of structural Y chromosome aberrations may be clinically important for genetic counseling and assisted reproductive technology treatment.

Abnormal non-invasive prenatal test results concordant with karyotype of cytotrophoblast but not reflecting abnormal fetal karyotype

“…The deletion of only Yq11.221‐>qter (AZFbc region, heterochromatin and PAR2), the (near) absence of cells with monosomy X in amniotic fluid, the small region between the centromeres on the isodicentric chromosome Y and the normal male genitalia seen on ultrasound, made the prognosis favorable. The male infant was expected to be infertile.…”

Rare case of monocentric isochromosome Y with inversion duplication of p arm in patient diagnosed with azoospermia

“…The occurrence of isochromosome Y coupled with mosaicism is relatively common in present literature but the presence of inversion duplication of the p arm of the second Y chromosome has not been widely reported. The occurrence of such derivative Y chromosome involving segmental duplication is rare and may involve sister chromatid rearrangements (Kim et al, ).…”

“…The genes on the Y chromosome are particularly crucial in the process of spermatogenesis. A variety of abnormalities, such as inversions, deletions translocations, dicentric Y and isochromosome Y, can lead to varying clinical symptoms such as testicular hypoplasia or developmental malformations, severe oligozoospermia and azoospermia (Kim et al, ; Li et al, ).…”

Isodicentric Y mosaicism involving a 46, XX cell line: Implications for management

“…The twin patients described here provide a novel look at the phenotype associated with mosaic isodicentric Y in conjunction with a 46, XX cell line. Several studies investigated the correlation between isodicentric Y mosaicism and sex development, however, the clinical picture is complicated by the high frequency of 45, X cell line mosaicism [Hsu, ; Tuck‐Muller et al, ; DesGroseilliers et al, ; Lange et al, ; Cools et al, ; Kim et al, ; Mekkawy et al, ]. Only two individuals with a 46, XX female chromosomal complement and a mosaic isodicentric Y cell line have been reported [Nazmy et al, ].…”