Application of single nucleotide polymorphism array for the identification of pathogenic copy number variations in fetuses with malformations and women with an adverse reproductive history / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To apply single nucleotide polymorphism microarray (SNP array) for the detection of genome-wide copy number variations(CNVs) in fetuses with malformations and women with an adverse reproductive history, and to explore the correlation of rare CNVs with the clinical manifestations.</p><p><b>METHODS</b>Amniotic fluid and umbilical cord blood samples were collected from 314 women with singleton pregnancy. SNP array was performed on samples where chromosomal abnormalities were excluded after G-banding analysis.</p><p><b>RESULTS</b>Pathological CNVs were detected in 8.91% (28/314) of all samples, which included 11 duplications, 9 deletions, 4 loss of heterozygosity (LOH), and 4 conjoined deletions and duplications. The sizes of duplications and deletions were between 0.47 Mb and 16.7 Mb, and between 0.16 Mb and 13.3 Mb, respectively. Fifteen CNVs were mapped to the regions of microdeletion or microduplication syndromes or regions associated with clinical manifestations, while the remainder 13 were considered benign or variant of uncertain significance.</p><p><b>CONCLUSION</b>A proportion of fetuses with malformations and women with an adverse reproductive history may be attributed to CNVs, half of which are mapped with to the regions of well known syndromes. SNP array may facilitate discovery of new syndromes and provide a basis for genetic counseling and prenatal diagnosis.</p>

Prenatal diagnosis of a case of Pallister-Killian syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the clinical and genetic characteristics of Pallister-Killian syndrome and improve the diagnosis for this rare chromosomal disease.</p><p><b>METHODS</b>Standard G-banding was carried out for the patient and his parents. Single nucleotide polymorphism array (SNP array) for copy number detection was applied to identify chromosome microdeletion or microduplication. Interphase fluorescence in situ hybridization (FISH) and cytogenetic analyses of fibroblast cells were performed based on the Results of array.</p><p><b>RESULTS</b>The patient's G-banded karyotype has turned out to be 46,XY, whilst his parents were both normal. A duplication of the whole short arm of chromosome 12 was detected by SNP array in the child. The result of interphase FISH performed on interphase chromosomes derived from peripheral blood cells was nucish (RP11-104 b5, a19 RP11-956) × 4 [19/100］, whilst the karyotype of fibroblast cells was 47,XY,+i(12) (p10 [44]/46, XY[56].</p><p><b>CONCLUSION</b>By combining with clinical characteristics, SNP array, skin fibroblasts karyotype analysis and FISH can diagnose Pallister-Killian syndrome effectively.</p>