35

Abstract

The complete trisomy 9 is relatively rare due to high fetal mortality. He present here a malformed liveborn infant with a 47,XY, +9,inv(9)(p13;q13)mat karyotype. The infant presented:hydrocephalia,microphtalmia,small palpebral fissures,upward slanted eyes, ocular hypertelorism,broad base and prominent tip of the nose, low set posteriorly rotated malformed ears, micrognathia,incipient cleft lip,narrow and high arched palate,short neck,pterigium colli,narrow trunk,pectus excavatum,short limbs,hip dislocation, micropenis,criptorchidism,3rd phalange of 4th finger superposed over the 3rd and 2nd fingers in both hands,absent patella,joint limitation,and calcaneovalgus deformity. Death occurred two hours after birth. The post-mortem examination revealed:stenosis of aqueduct of Silvius,ventricular septal defect,left diaphragmatic hernia,marked bilateral pulmonary hypoplasia. The parental karyo-types revealed that the mother was a carrier of pericentric inversion of chromosome 9:inv(9)(p13;q13). Of the 6 liveborn infants with trisomy 9 previously reported in the literature,3 had also the same type of inverted chromosome 9,and one an enlarged 9qh+ segment,which were transmited from parental carries.In addition,these polimorphisms were also found to be associated with others cases of non-disjunction,such us:21,13,18 and 8.Although, these polimorphisms are considered non pathologic morphological variants,one wonders if during meiosis its presence is really so innocuo.