genetic terms

Question 1

Both alleles contribute to the phenotype of the heterozygote

Answer 1

codominance

Question 2

phenotype varies among individuals w/ same genotype

Answer 2

variable expressivity

Question 3

not all individuals w/ a mutant genotype show the mutant phenotype

Answer 3

incomplete penetrance

Question 4

one gene contributes to multiple phenotypic effects

Answer 4

pleiotropy

Question 5

increased severity or earlier onset of dz in succeeding generations

Answer 5

anticipation

Question 6

If a pt inherits or develops a mut in a tumor suppressor gene, the complementary allele must be deleted/mutated before cancer develops. This is not true of oncogenes.

Answer 6

loss of heterozygosity (2 hit hypothesis)

Question 7

Exerts a dominant effect. a heterozygote produces a nonfunctional altered protein that also prevents the normal gene product from fxning

Answer 7

dominant negative mutation

Question 8

Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance. measured in a population, not in a family, and often varies in different populations

Answer 8

linkage disequilibrium

Question 9

Presence of genetically distinct cell lines in the same individual. arises from mitotic errors after fertilization

Answer 9

mosaicism

Question 10

mutations at different loci can produce a similar phenotype

Answer 10

locus hterogeneity

Question 11

different mutations at the same locus produce the same phenotype

Answer 11

allelic hterogeneity

Question 12

presence of both normal and mutated mtDNA, resulting in variable expression in mt inherited dz

Answer 12

heteroplasmy