3p deletion syndrome
Type of disease: Developmental disability (both intellectual and physical disabilities) | Genetic, autosomal dominant | Rare conditions
3p deletion syndrome is a rare chromosome disorder characterized by a missing (deleted) part of the short arm of chromosome 3 (known as 3p). The signs and symptoms vary. Some affected people appear to have no features or mild features, but most have been more severely affected. Features of the condition may include low birth weight, small head size (microcephaly), trigonocephaly, poor muscle tone (hypotonia), intellectual disability, growth delay, ptosis of the eye, and small jaw (micrognathia). Other features that have been reported include polydactyly, kidney anomalies, congenital heart defects, ear anomalies, and gastrointestinal tract anomalies. The loss of several genes on the deleted part of the chromosome is responsible for the features of the condition. The range and severity of features sometimes depends on the size of the missing piece of the chromosome. The loss of a specific region called 3p25 is thought to cause many of the more common features. The deletion usually occurs for the first time in the affected person (called a de novo mutation) but it can be inherited from a parent. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.