Statistical evaluation of a new method to detect carriers of phenylketonuria.

40 positive heterozygotes and 43 controls were loaded with 200 mg phenylalanine per kilogram body weight. The aromatic acids excreted 2 hrs after the loading were quantified by gaschromatography. The amounts of mandelic acid (MA), 2-hydroxyphenylacetic acid (2HOPAA) and phenylpyruvic acid (PPA) were used for a discriminatory analysis. The MA concentration alone gives a better discrimination than the statistical analysis.