heterotaxy, visceral, 1, X-linked
X-linked visceral heterotaxy type 1 is a very rare form of heterotaxy that has only been reported in a few families. Heterotaxy is the right/left transposition of thoracic and/or abdominal organs. This condition is caused by mutations in the ZIC3 gene, is inherited in an X-linked recessive fashion, and is usually seen in males. Physical features include heart abnormalities such as dextrocardia, transposition of great vessels, ventricular septal defect, patent ductus arteriosus, pulmonic stenosis ; situs inversus, and missing (asplenia) and/or extra spleens (polysplenia).Affected individualscan also experience abnormalities in the development of the midline of the body, which can cause holoprosencephaly, myelomeningocele, urological anomalies, widely spaced eyes (hypertelorism), cleft palate, and abnormalities of the sacral spine and anus. Heterotaxia with recurrent respiratory infections are called primary ciliary dyskinesia.