Pedigrees & Abnormal Genetics - Vocabulary Flashcards

Vocabulary flashcards covering pedigrees, inheritance patterns, genetic mutations, common traits, and genetic technologies based on the lecture notes.

Pedigree

Chart that shows the presence or absence of a trait within a family across generations.

Genotype

The genetic makeup of an organism (e.g., TT, Tt, tt).

Phenotype

The physical characteristics of an organism (e.g., tall, blue eyes).

Dominant allele

An allele that is phenotypically expressed over a recessive allele in heterozygotes.

Recessive allele

An allele that is expressed only when paired with another recessive allele (no dominant allele is present).

Autosomal dominant

A trait located on an autosome that is expressed when at least one dominant allele is present; usually appears in multiple generations and affects both sexes.

Sex-linked trait

A trait located on one of the sex chromosomes (often X-linked); patterns differ between males and females.

Autosomal trait

A trait located on a non-sex chromosome (autosome).

X-linked trait

A trait located on the X chromosome; often shows different inheritance patterns in males and females.

Homozygous

Having two identical alleles for a particular gene.

Heterozygous

Having two different alleles for a particular gene.

Carrier

An individual who carries one copy of a recessive allele but is typically phenotypically normal.

Pedigree symbols

Standard symbols used in pedigrees (circle=female, square=male, shading=affected, etc.).

Affected with trait

Individuals in a pedigree who express the trait (often shown by shading).

Dominant trait in pedigrees

A trait that typically appears in every generation; at least one parent must have the trait.

Recessive trait in pedigrees

A trait that can skip generations; affected individuals usually have two carrier parents.

Freckles (F)

An autosomal dominant trait where F is dominant over f, so individuals with at least one F have freckles.

Sickle cell anemia

An autosomal recessive disease; genotype hh indicates disease, while H represents a healthy allele.

Hemophilia

An X-linked recessive bleeding disorder.

Tongue rolling

A dominant trait for the ability to roll the tongue; genotypes TT or Tt roll, tt does not.

Eye color genetics

Brown eye color is typically dominant to blue.

Color vision

Normal color vision versus color blindness (red-green); often discussed in inheritance patterns.

Rh blood group

Rh positive vs Rh negative blood types; inheritance follows specific patterns.

Cheek dimples

A commonly cited trait; presence of dimples often treated as a dominant trait.

Germline mutation

Hereditary mutation present in egg or sperm; passed to offspring and in every cell.

Somatic mutation

Acquired mutation occurring in body cells; not inherited by offspring.

Mutations

Changes in the nucleotide sequence of DNA; can be hereditary (germline) or acquired (somatic).

Genetic testing

Tests that detect genetic mutations; can be used for disease risk, carrier status, or embryo screening with IVF (often high accuracy).

Ethical issues in genetics

Privacy, ownership, abortion decisions, DNA patenting, and access to genetic information.

Gene therapy

Treatment that delivers corrective DNA into cells using a viral vector (e.g., adenovirus) to modify genetic information.

Adenovirus vector

A virus used to deliver therapeutic DNA into human cells.

mRNA

Messenger RNA; carries genetic information from DNA to the ribosome for protein synthesis.

Nuclear pore

A channel in the nuclear envelope through which RNA and DNA pass between nucleus and cytoplasm.

Capsid

The protein shell of a virus that encases its genetic material.