Dominant and Recessive Alleles in Genetics

Wild-Type Allele

Prevalent alleles in a population.

Mutant Allele

Altered alleles due to mutation.

Heterozygote

Individual with two different alleles.

Dominant Phenotype

Expressed trait from dominant allele.

Gain-of-Function Mutation

Produces new or enhanced phenotype.

Dominant-Negative Function

Inhibits normal protein function.

Haploinsufficiency

One functional allele insufficient for phenotype.

Multiple Alleles

More than two alleles for a gene.

Phenotype

Observable traits of an organism.

Epigenetics

Changes in gene expression without DNA alteration.

PKU

Autosomal recessive disorder affecting phenylalanine metabolism.

Sex-Linked Genes

Genes located on sex chromosomes.

X-Linked

Genes carried on the X chromosome.

Y-Linked

Genes carried on the Y chromosome.

Sex-Influenced Traits

Dominant in one sex, recessive in another.

Sex-Limited Inheritance

Traits expressed only in one sex.

Lethal Allele

Allele that can cause organism's death.

Essential Genes

Required for survival of an organism.

Nonessential Genes

Not required for survival.

Temperature-Sensitive Alleles

Function affected by temperature changes.

Incomplete Dominance

Heterozygote exhibits intermediate phenotype.

Codominance

Both alleles expressed equally in phenotype.

Overdominance

Heterozygote has advantage over homozygotes.

Sickle-Cell Anemia

Disorder caused by abnormal hemoglobin.

Hb Genotypes

Different combinations of hemoglobin alleles.

Carbohydrate Tree

Structure on RBC surface modified by alleles.

Antigens

Substances recognized by immune antibodies.

Lethal Allele Timing

Timing of lethal effect varies.

Creeper Allele

Lethal when homozygous, causes mild phenotype.

Manx Allele

Lethal as homozygote, affects tail length.