Chapter 4- Extensions of Mendelian Genetics vocabulary wildtype allele complete dominance incomplete (partial) dominance codominance overdominance multiple alleles lethal allele gene interactions pleiotropy epistasis epistatic gene hypostatic gene modified dihybrid ratios complementation analysis X-linkage hemizygous holandric heterogametic criss-cross inheritance chromosome theory of inheritance sex-limited inheritance sex-influenced inheritance penetrance expressivity genetic anticipation genomic (parental) imprinting