[SNP-chip technology for identification of origins for prenatally detected marker chromosomes].
OBJECTIVE
To determine the origin of 1 prenatally detected small supernumerary marker chromosome (sSMC) using SNP-chip technology, and to deduce the underlying mechanism.


METHODS
The fetal sample was subjected to karyotype analysis. The identified sSMC was subjected to genom wide scan using a SNP microarray chip. The results were validated with fluorescence in situ hybridization (FISH).


RESULTS
The karyotype of the fetus was determined as 46, X, +mar, which was verified by SNP microarray chip analysis as Yp11.2-11.3 duplication, along with loss of Yq11.2 region, FISH analysis has confirmed that the sSMC has derived from the Y chromosome.


CONCLUSIONS
The karyotype of the fetus was determined as 46, X, idic(Y) (pter→ p11.2::11.2→ pter). Regional deletion of Yq11.2 has been associated with male azoospermia. SNP chip analysis can exclude minor deletions and duplications with a size of more than 1 Mb, which may be applied for verifying difficult cases as well as microdeletion and duplication syndromes upon prenatal diagnosis.
Central Laboratory, The Central Hospital of Wenzhou, Zhejiang 325000, P. R. China. tsh006@163.com; jxlu313@163.com.
Xue-qin
XQ
Xu
Ping
P
Wang
Shao-hua
SH
Tang
Huan-zheng
HZ
Li
Zhao-ke
ZK
Zheng
Fan-ni
FN
Xie
Jian-xin
JX
Lv
D000328:Adult; D025063:Chromosome Disorders / Q000175:diagnosis* / Q000196:embryology / Q000235:genetics*; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D007621:Karyotyping; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011296:Prenatal Diagnosis
D005819:Genetic Markers