Prenatal Diagnosis of 17p11.2 Copy Number Abnormalities Associated With Smith–Magenis and Potocki–Lupski Syndromes in Fetuses

Smith-Magenis syndrome and Potocki-Lupski syndrome are rare autosomal dominant diseases. Although clinical phenotypes of adults and children have been reported, fetal ultrasonic phenotypes are rarely reported. A retrospective analysis of 6,200 pregnant women who received invasive prenatal diagnosis at Fujian Provincial Maternal and Child Health Hospital between October 2016 and January 2021 was performed. Amniotic fluid or umbilical cord blood was extracted for karyotyping and single nucleotide polymorphism array analysis. Single nucleotide polymorphism array analysis revealed six fetuses with copy number variant changes in the 17p11.2 region. Among them, one had a copy number variant microdeletion in the 17p11.2 region, which was pathogenically analyzed and diagnosed as Smith-Magenis syndrome. Five fetuses had copy number variant microduplications in the 17p11.2 region, which were pathogenically analyzed and diagnosed as Potocki-Lupski syndrome. The prenatal ultrasound phenotypes of the six fetuses were varied. The parents of two fetuses with Potocki-Lupski syndrome refused verification. Smith-Magenis syndrome in one fetus and Potocki-Lupski in another were confirmed as de novo. Potocki-Lupski syndrome in two fetuses was confirmed to be from maternal inheritance. The prenatal ultrasound phenotypes of Smith-Magenis syndrome and Potocki-Lupski syndrome in fetuses vary; single nucleotide polymorphism array analysis is a powerful diagnostic tool for these diseases. The ultrasonic phenotypes of these cases may enrich the clinical database.