Topic 1 Single Gene Inheritance

Question 1

What is classical genetics

Answer 1

Inheritance of traits (discovered by Gregor Mendel)

Question 2

What is molecular genetics

Answer 2

Study of RNA and DNA structure function and molecular control of gene expression

Question 3

What is meaning of wildtype

Answer 3

The most prevalent phenotype in a population

Question 4

What is a mutant phenotype

Answer 4

Deviation from Wildtype phenotype as a result of change in allelic dna sequence

Question 5

What is loss of function

Answer 5

Significant decrease or complete loss of functional gene product

Question 6

What is gain of function

Answer 6

Gene product acquires new function of expression increased above wildtype activity

Question 7

Incomplete dominance

Answer 7

Heterozygote display the intermediate phenotype, on all’s is not completely masking the other

Question 8

Codominance

Answer 8

The Heterozygote expresses both alleles, fighting for expression

Question 9

What is haplosufficient

Answer 9

To express WT trait you only need one WT allele. The mutation is recessive

Question 10

What is haploinsufficient

Answer 10

In a Heterozygote, the single WT allele cannot provide enough product for normal function. If you have one mutated allele that allele is shown and is dominant.

Question 11

Slashes are for _____
Semicolons are for ____

Answer 11

Alleles for genes on homologous chromosome
Alleles for genes on non homologous chromosomes

Question 12

What is meant by pure breeding

Answer 12

No matter how many times it self crosses the phenotype is always the same

Question 13

What do gametes contain

Answer 13

Only one allele from each gene pair

Question 14

What is equal segregation

Answer 14

Half of the gametes carry one member of gene pair half carry the other

Question 15

What symbols do you use for the dominant trait when writing out genotypes

Answer 15

Uppercase Letter of the recessive or mutant allele ex. Brown is recessive to red

B/B or B/b or b/b

Question 16

What is the genotype of a tester

Answer 16

Homozygous recessive

Question 17

What is the P arm of the chromosome
What is the Q arm of the chromosome

Answer 17

The shorter arm
The longer arm

Question 18

What is telocentric

Answer 18

When there is no p arm, centromere is at the very end of chromosome

Question 19

What are sister chromatids

Answer 19

Chromosomes from a duplication chromosome that share the exact same genetic info. Not the same as homologous chromosomes

Question 20

What are homologous chromosomes

Answer 20

2 or more Chromosomes that have the same genes but different alleles. One from mom one from dad. These are not sister chromatids

Question 21

How do you test for sex linkage?

Answer 21

Carry out a reciprocal cross that swaps the genotypes of the male and female (A/A a/a), if the phenotype ratios are different genes are sex linked

In the f2 both should be present in 3:1 ratio if the genes are inherited autosomal manner

Question 22

What is heterogametic
Homogametic

Answer 22

No matching pair (XY) male
Matching pair of sex chromosomes (XX) Female

Question 23

What is a propositus

Answer 23

The first member in family tree that is noticed by a geneticist (usually has disease)

Question 24

Autosomal recessive pedigree

Answer 24

Disease often shows up from unaffected parents (carriers) both have to be carriers
If both parents have the trait all children will have it

Question 25

Autosomal dominant pedigree

Answer 25

No skipping of generations (affected individual must have at least one affected parent)

Two affected parents can have unaffected kids but two unaffected parent can’t have affected kids

Question 26

What are polymorphisms
What are rare diseases

Answer 26

Carriers common
Carriers very uncommon

Question 27

What do we assume about rates disease when new ppl come into pedigree

Answer 27

The new person is not a carrier for the disease unless proven other wise

Question 28

X-linked recessive pedigree

Answer 28

More male’s than females affected

If father affected, none of offspring will be affected (assuming the mom isn’t a carrier)

All male offspring from affected female are affected

Question 29

X-linked dominant rare disease pedigree

Answer 29

All daughters of affected male affected
No sons of affected male affected (unless mother is carrier)

Heterozygous affected female produces affected male and female with equal probability

Question 30

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Answer 30

Cjdkje

Question 31

Cdr

Answer 31

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