TY - JOUR
T1 - Identification of an unusual marker chromosome by spectral karyotyping
AU - Huang, Bing
AU - Ning, Yi
AU - Lamb, Alien N.
AU - Sandlin, Constance J.
AU - Jamehdor, Mehdi
AU - Ried, Thomas
AU - Hartley, James
PY - 1998
Y1 - 1998
N2 - We ascertained a newborn girl with multiple congenital anomalies including severe hypotonia, cardiovascular defects, hearing loss, central nervous system anomalies, and facial anomalies. The infant died at 12 days. Cytogenetic analysis showed a de novo supernumerary marker chromosome. Fluorescence in situ hybridization (FISH) with a combination of chromosome specific alphasatellite probes and an all-human centromere probe failed to show hybridization to the marker, indicating that the marker chromosome lacked detectable alpha satellite sequences. Spectral karyotyping (SKY) was performed and showed that the marker was chromosome 15 in origin. This was confirmed by FISH with a 15q specific subtelomeric probe, which showed hybridization to both ends of the marker chromosome. Based on FISH information and G-banding pattern, the marker was determined to be an inverted duplication of 15q25-qter, leading to partial tetrasomy for chromosome 15. Although the marker chromosome lacked detectable centromeric alpha-satellite sequences, it seemed to have a functional centromere as it is mitotically stable. This observation is consistent with previous studies on acentric marker chromosomes, which suggested that the DNA sequence at the breakpoint could function similarly to alpha-satellite sequences once activated through marker formation.
AB - We ascertained a newborn girl with multiple congenital anomalies including severe hypotonia, cardiovascular defects, hearing loss, central nervous system anomalies, and facial anomalies. The infant died at 12 days. Cytogenetic analysis showed a de novo supernumerary marker chromosome. Fluorescence in situ hybridization (FISH) with a combination of chromosome specific alphasatellite probes and an all-human centromere probe failed to show hybridization to the marker, indicating that the marker chromosome lacked detectable alpha satellite sequences. Spectral karyotyping (SKY) was performed and showed that the marker was chromosome 15 in origin. This was confirmed by FISH with a 15q specific subtelomeric probe, which showed hybridization to both ends of the marker chromosome. Based on FISH information and G-banding pattern, the marker was determined to be an inverted duplication of 15q25-qter, leading to partial tetrasomy for chromosome 15. Although the marker chromosome lacked detectable centromeric alpha-satellite sequences, it seemed to have a functional centromere as it is mitotically stable. This observation is consistent with previous studies on acentric marker chromosomes, which suggested that the DNA sequence at the breakpoint could function similarly to alpha-satellite sequences once activated through marker formation.
KW - Alphasatellite sequence
KW - Centromere
KW - Fluorescence in situ hybridization
KW - Marker chromosome
KW - Spectral karyotyping
KW - Tetrasomy of chromosome 15
UR - http://www.scopus.com/inward/record.url?scp=0031772122&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031772122&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1096-8628(19981204)80:4<368::AID-AJMG12>3.0.CO;2-B
DO - 10.1002/(SICI)1096-8628(19981204)80:4<368::AID-AJMG12>3.0.CO;2-B
M3 - Article
C2 - 9856565
AN - SCOPUS:0031772122
SN - 0148-7299
VL - 80
SP - 368
EP - 372
JO - American journal of medical genetics
JF - American journal of medical genetics
IS - 4
ER -