title: A twin sibling with Prader-Willi syndrome caused by type 2 microdeletion following assisted reproductive technology: A case report.
abstract: Prader-Willi syndrome (PWS) is a neurobehavioral imprinting disorder, which arises due to an absence of paternally expressed genes within the 15q11.2-q13 region. This occurs via one of the three main genetic mechanisms, as follows: Deletion of the paternally inherited 15q11.2-q13 region, maternal uniparental disomy and imprinting defect. Recent studies have reported an association between imprinting disorders and assisted reproductive technologies (ART). The current study presents a 6-year-old female patient who is a dizygotic twin, in which one was born withde novomicrodeletion at 15q11.2-q13.1 followingin vitrofertilization. The patient had characteristic facial features including narrow bifrontal diameter, strabismus, downturned mouth, feeding problems and generalized hypotonia during infancy, developmental delay, mental retardation and rapid weight gain. Based upon phenotypic resemblance and the medical records, methylation-specific multiplex ligation-dependent probe amplification and array-based comparative genome hybridization analyses demonstrate type 2 microdeletion between breaking point 2 (BP2) and BP3, which occur fromMKRN3throughHERC2at 15q11.2-q13.1. To the best of our knowledge, the present study is the first to report a PWS case born following ART reported in South Korea. In addition to previous studies, the present study contributes to the consensus regarding genotype-phenotype comparisons in this respect.
authors.affiliation: Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Ji Yoon
authors.initials: JY
authors.lastname: Han
authors.affiliation: Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Joonhong
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Woori
authors.initials: W
authors.lastname: Jang
authors.affiliation: Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Hyojin
authors.initials: H
authors.lastname: Chae
authors.affiliation: Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Myungshin
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea.
authors.forename: Yonggoo
authors.initials: Y
authors.lastname: Kim
keywords: Prader-Willi syndrome; array-based comparative genome hybridization; assisted reproductive technology; methylation-specific multiplex ligation-dependent probe amplification; type 2 microdeletion