Genetic Mutations and Variation

These flashcards cover key concepts related to mutations, genetic variation, and DNA repair from the lecture notes.

A __ is any inheritable change in nucleotide sequence.

Mutation

Mutations are __ and spontaneous.

random

Polymorphism refers to any genetic __ among individuals in a population.

difference

The observable characteristics of an organism is termed __.

phenotype

Genotype refers to the __ makeup of a cell or organism.

genetic

Alleles are different versions of the same __.

gene

Mutations can be __, harmful, or beneficial.

neutral

The __ gene encodes a protein that is expressed in many cell types but is highly expressed in the brain.

HTT

Somatic mutations occur in __ cells and are not passed on to offspring.

body (nongamete)

A __ mutation occurs in gametes and is passed on to offspring.

germ-line

Point mutations change a single __.

nucleotide

Nonsense mutations create __ codons in the mRNA during translation.

stop

Insertions and deletions introduce __ that change the reading frame.

frameshifts

DNA damage can be caused by __ or UV light.

X-rays

One consequence of mutations in the b-globin gene (HBB) is __ disease.

Sickle Cell

Spontaneous mutations occur __.

randomly

Insertions or deletions that occur in multiples of three base pairs usually result in the __ of amino acids.

addition or deletion

The most important DNA repair mechanism is the proofreading ability of __.

DNA polymerase

Mutations are the source of genetic __.

variation

A __ mutation results in a change in the amino acid sequence.

nonsynonymous

The Philadelphia chromosome is associated with __.

leukemia

What is a mutation?

A mutation is any inheritable change in nucleotide sequence.

What does polymorphism refer to in genetics?

Polymorphism refers to any genetic difference among individuals in a population.

What is a genotype?

Genotype refers to the genetic makeup of a cell or organism.

What are alleles?

Alleles are different versions of the same gene.

What is the main consequence of mutations in the b-globin gene (HBB)?

One consequence of mutations in the b-globin gene (HBB) is Sickle Cell disease.