Genetic Counselling and Genetic Testing - Part 1

Question 1

chromosome abnormalities

Answer 1

• examination of a karyotype from cells obtained by amniocentesis or chorionic villus sampling
• some forms can be detected by DNA analysis of maternal blood

Question 2

cleft lip and palette

Answer 2

ultrasound

Question 3

cystic fibrosis

Answer 3

DNA analysis of cells obtained by amniocentesis or chorionic villus sampling

Question 4

dwarfism

Answer 4

ultrasound or X-ray; some forms can be detected by DNA analysis of cells obtained by amniocentesis or chorionic villus sampling

Question 5

hemophilia

Answer 5

fetal blood sampling* or DNA analysis of cells obtained by amniocentesis or chorionic villus sampling

Question 6

Lesch–Nyhan syndrome

Answer 6

biochemical tests on cells obtained by amniocentesis or chorionic villus sampling

Question 7

neural-tube defects

Answer 7

initial screening with maternal blood test, followed by biochemical tests on amniotic fluid obtained by amniocentesis or by the detection of birth defects with the use of ultrasound

Question 8

osteogenesis imperfecta

Answer 8

ultrasound or X-ray (brittle bones)

Question 9

phenylketonuria

Answer 9

DNA analysis of cells obtained by amniocentesis or chorionic villus sampling

Question 10

sickle-cell anemia

Answer 10

fetal blood sampling* or DNA analysis of cells obtained by amniocentesis or chorionic villus sampling

Question 11

Tay–Sachs disease

Answer 11

biochemical tests on cells obtained by amniocentesis or chorionic villus sampling