["De novo" partial trisomy 16p (author's transl)].

An additional small G-like chromosome was found in a six-months old male with multiple congenital anomalies and marked mental retardation. GTG banding revealed that the index patient was trisomic 16 q1100 leads to pter. In the bibliographical review a few cases of partial trisomy of chromosome 16 have been reported so far, but only two of them affect the same chromosomic region of our case, and only one of them is "de novo", like ours: this one would be the first case in the spanish bibliography, according to our knowledge. The clinical findings in our patient are similar to the other two cases published: our purpose is to contribute with a new case to delimitate what seems to be a definite phenotypical outline associated with trisomy 16p. The two patients early reported were females, the propositus is the first case of trisomy 16p reported in a male liveborn with genital anomalies.