L29 Genetics and Pedigrees

Flashcards related to the concepts of genetics, specifically focusing on pedigrees and modes of inheritance.

Pedigree

A diagram of family relationships that uses symbols and lines to represent genetic relationships and traits of interest.

Modes of Inheritance (MOI)

The ways in which genetic traits are passed from parents to offspring.

Autosome

Any chromosome that is not a sex chromosome, determining traits independent of sex.

X-Linked Trait

A trait that is associated with a gene on the X chromosome.

Dominant Trait

A genetic trait that is expressed in the phenotype even when only one allele is present.

Recessive Trait

A genetic trait that is only expressed in the phenotype when two copies of the allele are present.

Allele

Different forms of a gene that can exist at a specific locus.

Heterozygote

An organism that has two different alleles for a specific gene.

Autosomal Recessive

A mode of inheritance where two copies of an allele are required to express a trait.

X-Linked Dominant

A mode of inheritance where only one copy of the allele on the X chromosome is sufficient to express the trait.

Obligate Heterozygote

An individual that carries one dominant and one recessive allele for a trait.

Inbreeding

Mating between closely related individuals, which can increase the chance of genetic disorders.

Albinism

A genetic condition characterized by a lack of pigment in the skin, hair, and eyes.

Legend

An explanation of the symbols used in a pedigree diagram.

Consanguinity

The property of being descended from the same ancestor as another person.

What do symbols in a pedigree represent?

Symbols in a pedigree represent individuals and their relationships, where circles typically denote females and squares denote males.

What is Autosomal Recessive inheritance?

Autosomal Recessive inheritance occurs when two copies of an allele (one from each parent) must be present for a trait to be expressed.

What is Autosomal Dominant inheritance?

Autosomal Dominant inheritance occurs when only one copy of an allele is needed for a trait to be expressed.

What is X-Linked Recessive inheritance?

X-Linked Recessive inheritance occurs when the allele causing the trait is located on the X chromosome, and males are more frequently affected.

What is X-Linked Dominant inheritance?

X-Linked Dominant inheritance occurs when a dominant allele on the X chromosome causes the trait to be expressed, affecting both males and females.

How can you interpret a pedigree to determine mode of inheritance?

To interpret a pedigree, look at the pattern of affected individuals across generations and analyze the gender distribution and transmission patterns.

What is involved in creating a pedigree from a family's medical history?

Creating a pedigree involves collecting data on family members' health history, noting traits and conditions, and mapping out relationships.