PATERNAL AGE AND DEVELOPMENT

Testicular ageing affects at the same time the individual and his line age. In the individual, vascular, endocrine, blood testis barrier and Sertoli cells changes because of age lead a decrease of spermatozoa nu mber and an alteration in their form and motility. These changes lead a gradual decrease of fertility. In the progeny, paternel ageing is re sponsible for new dominant autosomic mutations which themselves cause different malformations, as achondroplasia, Apert or Recklinghausen di sease, Marfan Syndrome etc. and perhaps for certain chromosome X linke d recessive mutations as Duchenne myopathy or hemophily A. Moreover in animal and man, paternal ageing seems reponsible for a gradual loweri ng in the level of progeny cerebral functions. In man, very youthful a ge is also related to these effects. Thus, the curve corresponding to this phenomenon presents an inverted U-Shape, of which the top corresp onds to about thirty years of paternal age. Maternal age does not appe ar to play a part in this event. On the whole, these results pose the problem of the optimum age for fatherhood.