Quantitative hematological characteristics in MZ and DZ twins.

The level of several biochemical hematological characteristics was determined--using colorimetric methods--in a group of 111 twins, aged 16-22 years. Significant variance differences between MZ and DZ twin pairs were observed in metabolites and serum enzyme levels. The intrapair differences of the variance of ions and protein levels were comparable in MZ and DZ twins. The validity of quantitative determination of heterability of biochemical characteristics is discussed.