Excuse me , that the baby is a heterozygote is two-thirds ?

那幺，那个孩子是杂合子的概率是2/3么？

Many of the so-called inborn errors of metabolism are inherited as a recessive trait - i.e. are apparent only in the homozygous individual , although sometimes the symptomless heterozygote can be identified by demonstrating subnormal activity of the gene product .

许多所谓的后天性代谢错误有隐性遗传特性，即仅在纯合子个体才显现，但是有时无症状的杂合体也能通过证明其基因产物活性低于正常来识别。