Provocative observation in the PKU collaborative study.
D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010661:Phenylketonurias / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics; D012730:Sex Chromosomes; D012737:Sex Factors; D012744:Sex Ratio; D014481:United States