The semi-lethal phenotype of mod(mdg4)eGp4 is fully complemented by mod(mdg4)Z3-5578 and mod(mdg4)Z3-3298, but mod(mdg4)eGp4 fails to complement these alleles with respect to X-Y chromosome nondisjunction in male meiosis - the transheterozygotes show a high level of X-Y nondisjunction (frequency is indicated in parentheses after each allele); mod(mdg4)Z3-5578 (50.3%) and mod(mdg4)Z3-3298 (49.0%).
The semi-lethal phenotype of mod(mdg4)eGp4 is fully complemented by mod(mdg4)Z3-3401, and mod(mdg4)eGp4 partially or fully complements mod(mdg4)Z3-3401 with respect to X-Y chromosome nondisjunction in male meiosis - transheterozygotes show only a low level of X-Y nondisjunction (2.94%).