genetics

Question 1

how is screening for Down syndrome carrier out ?

Answer 1

maternal age
triple screening
CUBs screening
selection for amniocentesis

Question 2

what are common recessive disorders that raise screening issue s?

Answer 2

CF
sickle cell disease 
thalassaemias
Ashkenazi jews
Tay-Sachs disease
breast/ovarian cancer

Question 3

how is CF diagnosed ?

Answer 3

immunoreactive trypsin - first 6 weeks
sweat test
genotyping

Question 4

what is Tay-Sachs disease ?

Answer 4

hexosaminidase A deficiency results in build up of lipid GM in nerve cells in the brain

Question 5

how does Tay-Sachs disease present ?

Answer 5

baby develops normally until 6 months of age
progressive neurological deterioration
fatal by 3-5 years

Question 6

what is screening in the 5 day blood spot test ?

Answer 6

phenylketonuria 
congenital hypothyroidism 
sickle cell disorders
CF
MCADD

Question 7

what is phenylketonuria ?

Answer 7

recessive

unable to break down phenylalanine

Question 8

how does PKU present and how is it treated ?

Answer 8

serious irreversible mental disability

controlled diet started by 21 days of age

Question 9

what is MCADD ?

Answer 9

medium chain acetyl Co-A dehydrogenase deficiency
recessive
cannot break down fat
can be life threatening

Question 10

how do you treat MCADD ?

Answer 10

prevent metabolic crisis - avoid fasting

glucose polymer and IV dextrose