[The Patau syndrome].

Known as D trisomy, Patau syndrome is the third chromosomopathy according to frequency. One of the 5000 newborn carries the trisomy 13. In over 80% cases there is fresh mutation with non separation in myeosis of older mother. The mosaic or translocation forms are not rare. The mail newborn with Patau syndrome is shown in this article. We notice: microcephalia, dolihocephalia, microphthalmia, cheilognatopalatoshisis, polydactilia, and found ultrasound changes at the brain, hearth and genitourinary system. Cytogenetic finding show: mail cariotype with aberrations 47, XY + 13, Sy Patau.