Genetics

Question 0

Chromosome abnormalities can be seen in _____% of all newborns

Answer 0

0.5%

Question 1

Normal Hans have how many chromosomes?

Answer 1

46

23 maternal and 23 paternal.
Gonads have 23

Question 2

What three chromosome abnormalities are associated with excessive growth?

Answer 2

Fragile X
XXY
XYY

Question 3

Prenatal diagnosis of chromosome abnormalities are found during amniocentesis at ______ weeks of pregnancy and by chorionic villus sampling at ______ weeks of gestation

Answer 3

14-16

9-10

Question 4

Name the infectious agents associated with malformation and chromosome abnormalities.

Answer 4

TORCHES

Toxoplasmosis 
other: varicella or parvovirus. 
Rubella virus
Cytomegalovirus 
HErpes virus/HIV
Syphilis

Question 5

Name the drugs associated with malformation congenital (5)

Answer 5

Alcohol 
Cocaine
Anticonvulsants - VPA
Warfarin 
Vitamin A derivatives

Question 6

What two maternal disorders can lead to malformations

Answer 6

Dm

Pku

Question 7

What three uterine factors could cause congenital malformation

Answer 7

Malformed uterus
Twinning
Polyhydramnios

Question 9

6 indications for referral for genetic counseling

Answer 9

1. Birth defects/MR/developmental delay
2. Dysmorphic child
3. Parent or sibling affected with known or suspected genetic disorder
4. Positive family history of birth defects especially if multiple members are affected
5. Possible teratogenic exposure
6. Advanced maternal age (>35 years)

Question 10

Which pathology?

upward slant of palpebral fissures
Brushfield spots of iris
protruding tongue
third fontanelle
low-set auricles
excess nuchal skin
single palmar (simian)crease
single flexion crease and incurving (clinodactyly) of 5th finger
increased distance between 1st and 2nd toes
mottling of skin
hypotonia
congenital heart disease - endocardial cushion defect, VSD

Answer 10

trisomy 21

down syndrome

Question 11

Which pathology?

Intrauterine growth retardation (IUGR) 
short palpebral fissures
small mouth
micrognathia
low-set abnormal auricles
prominent occiput
short sternum
abnormal position of the fingers (second overlapping 3rd and 5th overlapping 4th)) 
hypoplastic fingernails
rocker-bottom feet,
CHD
spasticity
feeding problems/failure to thrive

Answer 11

trisomy 18

Edwards syndrome

Question 12

Which pathology?

IUGR all three paremeters
coloboma of iris (pupil of keyhole shape) 
capillary hemangioma
skin defect of skull
hyperconvex nails
polydactyly
rocer-bottom feet
arrhinencephaly
cleft lip and palate
congenital heart disease
urinary tract abnormalties

Answer 12

Trisomy 13

Patau’s syndrome

Question 13

which pathology?

short stature
triangular face
abnormal shape of ears, webbed neck
broad shield chest
wide set nipples
congenital lymphedema of hands and feet
shortened 4th and 5th metacarpals and metatarsals
cubitus valgus
primary amenorrhea
CHD especially coarctation of aorta
mostly normal IQ
infertility

Answer 13

turner’s syndrome

45 X

Question 14

which pathology?

tall stature
post-pubertally small testicles
gynecomastia
eunuchoid build
increased risk for mild mental retardation (MR) 
learning and behavior problems
infertility

Answer 14

Klinefelter’s syndrome

47 XXY