Betaninuria: a genetic trait?

A total of 58 MZ and 41 DZ Hungarian adult like-sexed twin pairs were studied for the presence of betanin in urine (called betaninuria) after the ingestion of a standardized beetroot juice. By means of a semi-quantitative technique, betaninuria values of all test persons were determined. Several mathematical models were tested to find a probability distribution fitting well to the empirical data. The hereditary character of the intensity of betaninuria cannot definitely be accepted although some circumstances pointed to the effect of genetic factors on the phenomenon.