First Trimester Diagnosis of Holoprosencephaly Secondary to a Ring Chromosome 7

• Published in: Case reports in genetics Vol. 2013; no. 2013; pp. 1 - 3
• Main Authors: Henderson, Lindsay B., Corson, Virginia L., Saul, Daniel O., Anderson, Cynthia, Millard, Sarah, Batista, Denise A. S., Blakemore, Karin J., DeScipio, Cheryl
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Puplishing Corporation 01-01-2013; Hindawi Publishing Corporation; Hindawi Limited
• Subjects: Case Report
• ISSN: 2090-6544; 2090-6552
• DOI: 10.1155/2013/578202

Holoprosencephaly (HPE) is a developmental defect in humans in which the forebrain fails to completely separate into two hemispheres. We describe a 12 3/7-week-old fetus found on ultrasound evaluation to have features consistent with HPE, including a single anterior ventricle, fused thalami, and a flattened profile. Cytogenetic analysis of chorionic villi revealed a ring chromosome 7 [r(7)]. This uncommon finding has been associated with growth delay, microcephaly, and dermatologic abnormalities. However, both the clinical features and the extent of cytogenetic imbalance of chromosome 7 are variable, and few reported cases of r(7) have been molecularly studied. To our knowledge, this is the first report of a prenatally identified r(7), molecularly characterized using array comparative genomic hybridization.