The Effect of Previous History of PKU on the Average Detection Age of Sibs and Close Relatives

  SUMMARY In this paper the effect of previous history of PKU in sibs and close relatives on the average age of the disease detection is studied . To find out the effect of the previous case of PKU on the detection age of her I his younger sibs, the population of 93 PKU patients were divided into 2 distinct group-I includes 63 patiens, that are the only or the first PKU children of their parents. Group -2 includes 30 patients that are the second third, or forth PKU children of their parents. Group-2 arc the patients whose parents hav, had one or more PKU children before their birth. The mean detection age of group -1 and 2 arc28.4 and 14 months respectively and their difference is significant (p < 0.001) . Although the mean detection age of group -2 is about the half of the group -I nevertheless the disease in most of the patients of the second group were detected so late that they were already suffering from some degree of mental retardation too. To find out the effect of the previous history of PKU in kindreds on the mean detection age of the later born PKU patiens, the group -1 was divided into 2 subgroups: Group -1-1 that includes the first and group 1-2 includes the second, third, cct. PKU patients in the kindreds. The mean detection age of the subgroup 1-1 and 1-2 arc 28 and 28.7 months respectively, and their difference is not significant. (P>0.4). The result of this study indicates that: 1)The previous history of PKU in sihs reduces the average age of disease detection of the younger cases to ahout half. 2)The Previous history of PKU in the kindred has no significant effect on the average age of the younger PKU patients of the kindred.