or Patau's syndrome caused by meiotic nondisjunction; major clinical findings include abnormal brain development, cleft palate and postaxial polydactyly.

a genetic disorder in which an individual has an extra 13th chromosome, characterized by mental retardation and malformed ears in all patients, and in most patients cleft lip or palate, small mandible, polydactyly, cardiac defects, convulsions, renal anomalies, intestinal malrotation, and dermatoglyphic anomalies; the condition is usually fatal within several weeks or months of birth

A chromosomal (genetic) disorder where there is and extra copy of all or part of Chromosome 13 leading to a series of birth defects. For more information see the Factsheet on Trisomy 13.