Genetics

Question 1

Causes of congenital abnormalities?

Answer 1

Environmental: Drugs, Alcohol, infections, maternal diabetes

Genetic: Monogenic or polygenic

Question 2

What is Aperts syndrome?

Answer 2

Complete fused digits

Question 3

What is pierre-roberts syndrome?

Answer 3

Very small jaw with possible airway obstruction and cleft lip/palate

Question 4

Difference in a full mutation and a premutation?

Answer 4

Full mutation is likely to cause the defect in the affected person and a pre-mutation can potentially cause the defect in offspring

Question 5

What gender can fragile x affect? what are the symptoms?

Answer 5

Male only - mental retardation

Question 6

What causes fragile x?

Answer 6

Repetition of the CGG tri-nucleotide sequence of above 200 repeats

Question 7

What is spinal muscular atrophy?

Answer 7

Severe autosomal recessive genetic condition resulting inability of babies to develop muscles properly and early death.

Question 8

So if Mary carries a premutation of 100% chance of developing fragile x on one allele and a 0% on the other, what is the chance her baby (of unknown gender) will have fragile x?

Answer 8

1 in 4 - 50% chance of passing on affected allele and 50% chance of boy.

Question 9

Genetic test to determine fragile x syndrome?

Answer 9

PCR