If this were the case, we would expect other mua genes to encode additional components of the proposed regulatory pathway. To test this conjecture, we are cloning additional mua loci.
Earlier stages are unaffected.
Additional alleles are being sought via non-complementation screens, both to identify the null phenotype and to obtain higher penetrance alleles that will assist in assaying for cosmid rescue. We are further refining the map positions of both genes preparatory to obtaining and microinjecting cosmids. We will be reporting our progress in the identification of rescuing cosmids and candidate genes.