Advanced Mendelian Genetics

Question 1

What are alleles

Answer 1

Different variants of the same genes

Question 2

What is a locus

Answer 2

The region of DNA where alleles of a gene correspond to

Question 3

Define dominant allele

Answer 3

Allele that produces an effect on the phenotype when present in either one or two copies (PP or Pp)

Question 4

Define recessive allele

Answer 4

An allele that produces an effect on phenotype only when there is no dominant allele present (pp)

Question 5

What is a wild type allele?

Answer 5

The strain that is most common in the wild

Question 6

Why is it okay to have one mutant allele and one normal allele when the gene codes for an enzyme?

Answer 6

Because in most cases, having half the amount of enzyme is enough to allow reaction to proceed as normal

Question 7

Define haplosufficient

Answer 7

When only one working copy is necessary/sufficient for normal expression of the gene’s function.

Question 8

Is the functional or non-functional (mutant) allele dominant in haplosufficiency?

Answer 8

The functional gene is the dominant one

Question 9

Which allele is dominant in haploinsufficency?

Answer 9

The mutant allele is dominant

Question 10

What will the phenotype of a heterozygous gene look like in haploinsufficency

Answer 10

Mutant phenotype (unlike haplosufficiency where one working allele would have been enough to produce normal phenotype)