UPD16 itself is not a cause of intrauterine growth restriction

Abstract

Background: The clinical relevance of uniparental disomy (UPD16) for chromosome 16 is currently unclear. Methods and result: We performed chromosome microarray analysis on two fetus and their placentas, fluorescence in situ hybridization (FISH) to exclude the hidden chr16 trisomy mosaicism in the fetuses, and clinical whole-exome sequencing to assess for homozygosity mutations of autosomal-recessive diseases. Results: Microarray analysis of two fetuses had UPD16. The membranous placenta of the case 1 had confined placental mosaicism (CPM) for trisomy 16. Clinical whole-exome sequencing on chromosome 16 revealed three potentially pathogenic single nucleotide polymorphisms (SNPs). Gap-polymerase chain reaction (PCR) and MLPA for a-thal deletions demonstrated that case 2 was homozygous for the –SEA deletion. Conclusions: The poor outcome in these fetuses may be attributed to other factors, the membranous placenta and the –SEA deletion, respectively. Fetal UPD16 itself might be not correlated with intrauterine growth restriction (IUGR) and thus is not the basic cause of IUGR.

Keywords:

• uniparental disomy
• membranous placenta
• intrauterine growth restriction
• clinical whole-exome sequencing
• chromosome microarray analysis

Additional information

Funding

This study was supported by Provincial Science and Technology Plan Project of Guangdong Province (the Sino-U.S. Joint Development Defects Transformation Medical Center Construction; 2015B050501006 to ZhongMei); by Shunde District Science and Technology Plan Project (South Wisdom Valley Innovative Research Team Program, 2015CXTD06 to ZhongNa); by Shenzhen Science and Technology Innovation Committee (Relationship between Placental Tissue Copy Variation and Intrauterine Growth Restriction; JCYJ20170413092818116 to Xie Jiansheng).