Genetics and X-Chromosome Inactivation

Flashcards covering key genetic concepts and terms related to heredity, X-chromosome inactivation, and genetic mutations.

Androgen Insensitivity Syndrome

A condition where individuals with male XY chromosomes develop female physical characteristics due to an inability to respond to testosterone.

CAG repeat expansion

A genetic mutation involving the repetition of the sequence cytosine-adenine-guanine, often leading to disorders such as androgen insensitivity syndrome.

Skewed X chromosome inactivation

The process where one X chromosome is preferentially activated over the other in female cells, affecting gene expression.

XIST RNA

A non-coding RNA that plays a crucial role in the process of X chromosome inactivation by coating one of the X chromosomes and silencing it.

Primary nonrandom X-inactivation

A scenario where certain factors influence the preferential inactivation of either the maternal or paternal X chromosome.

Secondary nonrandom X-inactivation

In this case, the initial choice of X inactivation is random, but later cell divisions favor one X chromosome due to a gene on it.

Meiosis

A specialized type of cell division that reduces the chromosome number by half, resulting in the production of gametes.

Heredity

The transmission of genetic characteristics from parents to offspring, influencing traits and diseases.

Penetrance

The proportion of individuals with a genotype that exhibit the associated phenotype.

Polygenic inheritance

A type of inheritance where multiple genes influence a trait, leading to a range of phenotypes.

Genetic imprinting

A genetic phenomenon whereby certain genes are expressed in a parent-of-origin-specific manner.