Prenatal diagnosis of two fetuses with de novo small supernumerary markers by single nucleotide polymorphism array based comparative genomic hybridization / 中华医学遗传学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To explore the origins of small de novo mosaic supernumerary marker chromosomes (mars) in two fetuses, and to assess the feasibility of single nucleotide polymorphism array-based comparative genomic hybridization (SNP-array CGH) for prenatal molecular cytogenetic diagnosis.</p><p><b>METHODS</b>Two fetuses with de novo were identified. SNP-array marker chromosomes was applied to define the location and range of marker chromosomes. The karyotype of fetus I was determined to be 47,XX,+ mar[23]/46,XX[16], and that of fetus II was 47,XX,+ mar. Multiplex ligation-dependent probe amplification (MLPA) was applied to verify the genomic imbalance found in fetus II. The karyotypes of parents were normal in both families.</p><p><b>RESULTS</b>SNP-array CGH has indicated a 8.3 Mb duplication at 9p21.1-p21.3 in fetus I, and a 10.8 Mb duplication at 15q11.2-q13.3 in fetus II. MLPA has also confirmed a 15q terminal duplication in fetus II.</p><p><b>CONCLUSION</b>Above cases have illustrated that SNP-array CGH is a rapid, powerful and sensitive technique which may be used for identify the origins of marker chromosomes in prenatal diagnosis.</p>