Two cases of tetrasomy 9p syndrome with tissue limited mosaicism.
Tetrasomy of short arm of chromosome 9 constitutes a clinically recognizable chromosomal syndrome. Isochromosome 9p shows a strong propensity to tissue-limited mosaicism. It occurs predominantly in peripheral blood cultures, often at a lower frequency or even absent in skin, amniotic fluid or chorionic villous cell cultures. Tissue-limited nature of mosaicism may render prenatal detection of this condition very difficult. Herein, we report two new cases of mosaic tetrasomy 9p. Conventional cytogenetics (CC) and FISH studies demonstrated a differential expression of the mosaicism in several tissues. We review the literature and discuss the implications of these findings in cytogenetic prenatal diagnosis.
Lloveras
Elisabet
E
Departament de Citogenética, General Lab-Laboratoris d'Anàlisis, C/Londres no. 45, 08036 Barcelona, Spain. elilloveras@hotmail.com
Pérez
C
C
Solé
F
F
Zamora
L
L
Lladonosa
A
A
Espinet
B
B
Silvestre
E
E
Serra
J
J
Vendrell
T
T
Fernández
B
B
Salido
M
M
Plaja
A
A
D000782:Aneuploidy; D002675:Child, Preschool; D025063:Chromosome Disorders / Q000175:diagnosis* / Q000235:genetics; D002899:Chromosomes, Human, Pair 9; D020732:Cytogenetic Analysis; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018404:Isochromosomes / Q000235:genetics; D008297:Male; D009030:Mosaicism / Q000235:genetics* / Q000473:pathology; D011296:Prenatal Diagnosis; D013577:Syndrome