What are the lethal genes?
The Lethal genes are genes having at least one allele that, while present in the genotype of an individual, causes death. There are dominant lethal alleles and recessive lethal alleles. (There are as well genes having alleles that are dominant when in heterozygosity but lethal when in homozygosity that is the dominance related to the phenotype does not correspond to the dominance related to lethality.)