Patau Syndrome (Trisomy 13) [Q91.4]
Dipl.-Biol. Uwe Heinrich
The incidence of the Patau syndrome is on average 1 in 5,000 newborns. In 75% of all cases, a free trisomy 13 is found, in 5% a mosaic trisomy and in 20% an unbalanced translocation. Characteristic physical malformations usually include a bilateral cleft lip/palate, various eye defects (micro or anophthalmia, coloboma), microcephaly, hexadactylia, dysplastic ears, scalp defects and omphalocele. Organic defects include cardiac defects, cystic kidneys and CNS anomalies such as arhinencephaly or holoprosencephaly. The psychomotor development is severly impaired. Approximately 50% of all patients decease within the first month of life, over 90% within the first year.