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Updated: Jan 20, 2026

Fluorescence In Situ Hybridization on DNA Halo Preparations to Reveal Whole Chromosomes, Telomeres and Gene Loci
Published on: March 4, 2021
Telomeric association between chromosomes Y and 19 in a mosaic Turner with primary ovarian insufficiency
Linda C Barnabas1, Kundavi Shankar2, Bibhas Kar1
1Center for Genetic Studies & Research, The Madras Medical Mission, Chennai, India.
Abstract:
A rare case of telomeric association between Y and 19 chromosomes in a 24-year-old patient with primary ovarian insufficiency is being reported. Clinical evaluation revealed a webbed neck, high-arched palate and short stature with absence of axillary hair. Small uterus and streak gonads were noted on pelvic ultrasonography. Cytogenetic analysis showed a mosaic karyotype 46,X,tas(Y;19)(p11.3;q13.4)/45,X with two centromeres on the derivative chromosome. Fluorescence in situ hybridization (FISH) for X and Y centromere, SRY gene and subtelomeric FISH showed that signals for SRY and heterochromatin of Y chromosome were found at the base of chromosome 19 and the subtelomere regions of 19q and Yp were intact. Multiplex polymerase chain reaction was done to check for common microdeletions in AZF region and showed no microdeletion. Due to the presence of Y chromosome, laparoscopic examination followed by gonadal histopathology was done and confirmed the presence of ovotestes. Gonadectomy was performed to avoid future risk of gonadoblastoma. Artificial reproductive techniques using donor oocytes was suggested to the couple.
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