Epigenetics

Question 1

What enzymes responsible for histone modifications?

Answer 1

histone acetyl transferase (HATs), histone methyltransferase (HMTs), and histone kinase

Question 2

What enzymes reverse histone modification?

Answer 2

histone deacetylase (HDACs), histone demethylases, and histone phosphatases

Question 3

Prader Willi Syndrome

Answer 3

Expression of dad’s methylated chromosome 15 as mom’s is deleted= poor feeding then excessive feeding leading to obesity, poor affect, mild cog. impairments

Question 4

Angleman Syndrome

Answer 4

Expression of mom’s methylated chromosome 15 (dad’s is deleted)= ataxia, happy affect, severe cognitive impairment, hand flapping

Question 5

How do you calculate allele frequency?

Answer 5

number of copies of a specific alleles in a population/total number of ALL alleles FOR that GENE in the population
ex)
Freq. of recessive allele= [(Tt) + 2(tt)]/ [2(TT) + 2(Tt) + 2(tt)]
[1(42) + 2(9)]/ [2(49) + 2(42) + 2(9)]
q=0.3 or 30%

Question 6

How do you calculate gene frequency?

Answer 6

Gene freq=# of individuals w/ a particular genotypes in a population/number of individuals in that population
Freq. of homozygous recessive (tt)= 9/49+42+9