Can an MZ be liver affected as a child?

Alpha (1)-antitrypsin deficiency is a common genetic disease in which individuals homozygous for the mutant Z allele are at risk for the development of liver disease and emphysema…

The heterozygous carrierAn Alpha-1 Carrier is a person who has one normal ATT gene (M) and one defective AAT gene (usually S or Z). It does NOT mean you cannot get sick. state for the mutant Z gene, present in 1.5% to 3% of the population, is not itself a common cause of liver injury but may be a modifier gene for other liver diseases.

PubMed.gov – Dr. J Teckman