Recessive Lethal Allele

Lethal as a homozygote but has no effect on viability in the heterozygous condition.

1:1 Phenotypic Ratio

The outcome of a heterozygote by recessive homozygote cross.

Co-dominance

The heterozygote has two functional alleles.

Pleiotropy example

Recessive Lethal Alleles

Autosomal

Not a sex chromosome

Anaphase 1

Partly responsible for independent segregation

9:3:3:1 ratio

Expect for two genes, each with two alleles, dominance and sorting independently.

Incomplete Dominance

The heterozygote has an intermediate phenotype

Homologous chromosomes

Pair of chromosomes sharing 90% sequence identity

1:1 Genotypic Ratio

The outcome of a heterozygote by homozygote cross.

Allele

A variant of a gene