Genetics

Question 1

What is genetic sex bias?

Answer 1

When the first child affected is of the less common sex, subsequent children of the more common sex are more likely to have the trait

Question 2

Rett syndrome

Answer 2

almost always in females
hemizygous MECP2 variant
regression of speech and motor milestones after 6-18mo

Question 3

Most common genetic association with schizophrenia?

Answer 3

22q11 deletion (DiGeorge)

Question 4

P-value for a genome wide association study?

Answer 4

5e-8

Question 5

Main mechanism for gene or chromosome inactivation?

Answer 5

methylation

Question 6

What is the genetic mechanism of fragile X?

Answer 6

triplet repeat in non-coding region increases methylation and silences gene

Question 7

Prader-Willi Syndrome presentation?

Answer 7

0-2 yrs - hypotonia, poor feeding
2-6 yrs - overweight
6-12 yrs - hyperphagia, obesity, compulsive behavior

Question 8

Angelman Syndrome presentation?

Answer 8

microcephaly, seizures, frequent inappropriate laughter