By means of the analysis of the geographical distribution of the birth-places of cases with phenylketonuria, who were detected in a nation-wide screening for phenylketonuria by the Guthrie test during a period of more than 5 years, 3 areas with a remarkably different frequency can be recognized: a) in the districts of Cottbus, Leipzig, Halle and Frankfort the frequency of the phenylketonuria is amounting to 1:6275, of the phenylketonuria-gene to 0.0126 and of the heterozygotes to 2.49%; b) in the remaining districts with the exception of two districts the frequency is significantly lower (1:11272, 0.0094, 1.86%); c) in the districts of Karl-Marx-Stadt and Neubrandenburg this metabolic disease is relatively rare (1:14769, 0.0082, 1.63%). In regions with a high frequency of the phenylketonuria the permanent mild hyperphenylalaninaemia is also twice more frequent than in the remaining country.

Gene Frequency↗

PubMed1975

[Prenatal brain damage in maternal, untreated phenylketonuria].

Several reports in literature exist about mentally retarded non-phenylketonuric offspring from untreated phenylketonuric mothers with normal intelligence. One additional case is added who was detected after screening of about 1600 pregnant women. Biochemical investigations of the mother identified her as "classical phenylketonuria". Column chromatographic analysis of amino acids in amniotic fluid revealed a very high pheylalanine level and the diminution of the other, especially essential amino acids. The estimated amino acids in fetal brain also revealed a very high phenylalanine level. Routine screening for phenylketonuria by means of the Guthrie's test is recommended for all pregnant women at the first visit of the counseling.

Amino Acids↗

PubMed1975

[Determination of kynureninase activity in oligophrenic children with hereditary taint, before and after vitamin B6 treatment].

Kynureninase activity assay in oligophrenic children with hereditary taint, before and after treatment with vitamin B6. The hepatic kynureninase activity was assayed in 25 oligophrenic children with hereditary taint, and having a positive tryptophan load test. Eight cases (32%) showed an enzyme activity below the 2-s limit; in two cases, the pathologic enzyme activity could be almost normalized by addition of higher P-5-P concentrations. In a second set of studies, eight children with an abnormally low kynureninase activity were re-examined following a 3-week treatment with vitamin B6. The enormous in-vivo-activation of kynureninase reached in these studies lends support to the assumption of a vitamin-B6-dependent "inborn error of metabolism" in the tryptophan-kynurenin pathway in some of the investigated oligophrenic children with hereditary taint.

Adolescent↗

PubMed1975