Unexpected retention and concomitant loss of subtelomeric regions in balanced chromosome anomalies by FISH.
Florescence in situ hybridization (FISH) using subtelomeric probes has been useful in detecting cryptic telomeric chromosomal rearrangements. We report, for the first time, that cytogenetically visible chromosome rearrangements can occur between the subtelomeric and telomeric region in clinically normal individuals with balanced chromosome anomalies in which one of the breakpoints involves a terminal band region. Using FISH with subtelomeric probes, we observed in three cases with a balanced reciprocal translocations the retention and subsequent loss of subtelomeric regions. In one case with a paracentric inversion, there was a proximal relocation of a subtelomeric region. Because subtelomeric regions serve important roles in chromosome pairing, this retention and concomitant loss or relocation of a subtelomeric region could possibly further disrupt the complex meiotic configurations of these balanced chromosome rearrangements. This may then have an effect on gamete production, placing these individuals at a higher risk for miscarriages and/or abnormal outcomes for individuals with similar chromosome aberrations.
Pettenati
Mark J
MJ
Department of Pediatrics, Section on Medical Genetics, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA. pettenat@wfubmc.edu
Jackle
Bethy
B
Bobby
Peggy
P
Stewart
William
W
Von Kap-Herr
Chris
C
Mowrey
Philip
P
Rao
P Nagesh
PN
May
Kristin M
KM
D000026:Abortion, Habitual / Q000235:genetics; D000328:Adult; D000649:Amniocentesis; D002648:Child; D002869:Chromosome Aberrations; D025063:Chromosome Disorders / Q000235:genetics* / Q000473:pathology; D007446:Chromosome Inversion; D002877:Chromosomes, Human / Q000235:genetics / Q000648:ultrastructure; D005260:Female; D005333:Fetus / Q000002:abnormalities; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008607:Intellectual Disability / Q000235:genetics; D008540:Meiosis; D011247:Pregnancy; D016615:Telomere / Q000648:ultrastructure*; D014178:Translocation, Genetic