Familial small supernumerary marker chromosome (sSMC) (14)(:p11-q11:) [corrected] in a child with translocation Down syndrome.
We report a case of familial small supernumerary marker chromosome (sSMC)in a child with translocation Down syndrome (DS)and mother. The GTG-banded chromosomal analysis of DS child revealed 47,XY,+21,+mar and mother karyotype was 47,XX,+mar. The GTG-banded sSMC had a similar morphology of small acrocentric chromosomes. Fluorescence in situ hybridization (FISH)evaluation of sSMC using centromere probes(13/21,14/22,22)confirmed sSMC as derivative chromosome 14. The sSMC was not specifically stained with whole chromosome paint and arm-specific probes for chromosome 14;thus it has been described as der(14)(:p11-q11:).The phenotypic changes were not evident, may be due to trisomy condition in the child or the sSMC contain repetitive sequences.
Vundinti
Babu Rao
BR
Department of Cytogenetics, National Institute of Immunohematology (ICMR) K.E.M. Hospital Campus, Parel, Mumbai, India. vbaburao@hotmail.com
Korgaonkar
Seema
S
Ghosh
Kanjaksha
K
D000293:Adolescent; D002871:Chromosome Banding; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008297:Male; D014178:Translocation, Genetic / Q000235:genetics*; D014314:Trisomy / Q000235:genetics*