SNP array analysis of three cases with partial 21q trisomy.
- Author:
Lili ZHOU
1
;
Chong CHEN
;
Zhaoke ZHENG
;
Hao WU
;
Fanni XIE
;
Xiaoling LIN
;
Yanbao XIANG
;
Xueqin XU
;
Shaohua TANG
Author Information
- Publication Type:Journal Article
- MeSH: Child, Preschool; Chromosome Banding; Down Syndrome; genetics; Female; Genotype; Humans; Infant; Infant, Newborn; Male; Microarray Analysis; methods; Polymorphism, Single Nucleotide
- From: Chinese Journal of Medical Genetics 2017;34(6):861-865
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo analyze three cases with partial 21q trisomy, and correlate their genotypes with phenotypes.
METHODSG-banding chromosomal analysis and single nucleotide polymorphism (SNP array) were performed for the three cases and their parents.
RESULTSSNP array has detected partial 21q trisomy in three cases and one mother, with variable size and location of the duplications. Case 1 harbored a 12.35 Mb duplication at 21q22.11q22.3, which spanned the Down syndrome critical region. Case 2 harbored a 35.32 Mb duplication at 9p24.3p13.3 and a 14.42 Mb duplication at 21q11.2q21.3, with the former spanning the partial 9p trisomy syndrome critical region excluding the Down syndrome critical region, and was inherited from his mother. Case 3 harbored a 4.17 Mb tetraploidy at 21q11.2q21.1 in the form of mosaicism, which spared the Down syndrome critical region. His mother carried a 4.17 Mb triploidy at 21q11.2q21.1, which was also a mosaicism.
CONCLUSIONPartial 21q trisomy may occur in various forms and its clinical phenotypes are heterogeneous. Combined use of genetic techniques, particularly SNP array, is crucial for diagnosing partial 21q trisomy and delineating its genotype-phenotype correlation.
