Genetics

Question 1

What is the baseline risk for birth defects?

Answer 1

4% (1 in 25)

Question 2

Birth defect due to INTRINSIC abnormalities, such as genetics; examples are Polydactyly and Cleft Lip; during embryonic period

Answer 2

Malformation

Question 3

Birth defect due to EXTRINSIC factors that physically impinge on the fetus during development; examples are joint contractures and arhtrogyrposis (joint hooking); after embryonic period

Answer 3

Deformation

Question 4

Birth defect caused by alteration of cellular constitution or tissue organization

Answer 4

Dysplasia

Question 5

Birth defect due to the destruction of irreplaceable normal fetal tissue; usually due to amniotic bands and amputations

Answer 5

Disruption

Question 6

Cascade of events from a single primary cause; example is Potter Sequence (renal agenesis–> oligohydramnios–> pulmonary hypoplasia and limb anomalies)

Answer 6

Sequence

Question 7

Organogenesis is usually done by week…

Answer 7

Week 8 (embryonic period)

Question 8

Examples of Chemical Teratogens

Answer 8

Alcohol
Nicotine
Tetracyclines
Retinoic acid (Vit A)
Thalidomide

Question 9

Which teratogen can result in yellow staining of teeth and diminished growth of long bones

Answer 9

Tetracyclines

*STUDY AID: “Teethracyclines”

Question 10

Which teratogen can result in growth deficiency, intellectual disability, congenital heart defects and abnormal facial features (smooth philtrum, thin vermillion border, etc.)

Answer 10

Alcohol

Question 11

Examples of TORCHeS infections

Answer 11

Toxoplasmosis gondii
Other (Parvo and Varicella)
Rubella
CMV
HSV
Syphilis

Question 12

Obstetric/Fetal risks of Maternal Diabetes

Answer 12

Macrosomia
Caudal regression syndrome (legs)
Cardiac defects
neonatal hypoglycemia (hyperplasia of fetal islet cells)
Polycythemia

Question 13

How can Ehlers-Danlos Syndrome complicate pregnancies

Mutations in Type III collagen

Answer 13

Worsening symptoms
Rapid onset labor
Uterine rupture
Arterial dissection/rupture

Question 14

How can Marfan Syndrome complicate pregnancies

Answer 14

Valvular/Aortic complications

*HIGH risk

Question 15

Signs/Symptoms of Down Syndrome

Answer 15

• Flat facies
• Duodenal Atresia
• Broad nasal bridge
• Low-set ears
  Single palmar crease
  Heart defects
  Intellectual disability

Question 16

Chromosome 18 trisomy; Death by age 1 year; small head and jaw, low-set ears, profound intellectual disability and heart defects; CLENCHING of hands and ROCKER BOTTOM feet

Answer 16

Edward Syndrome

Question 17

Fancy name for Trisomy 18

Answer 17

Edward Syndrome

Question 18

Signs/Symptoms of Trisomy 18 (Edward Syndrome)

Answer 18

• STUDY AID: “PRINCE” Edward
• Prominent occiput
• Rocker bottom feet
• Intellectual disability
• Nondisjunction
• Clenched hands
• low-set Ears

Question 19

Chromosome 13 Trisomy; Death by age 1 year; intellectual disability, polydactyly, holoprosencephaly and cleft lip/palate

Answer 19

Patau Syndrome

Question 20

Signs/Symptoms of Patau Syndrome (Trisomy 13)

Answer 20

• STUDY AID: “P” atau syndrome
• Polydactyly
• cleft liP/Palate
• holoProsencephaly (failure of forehead development)
• cutis aPlasia (absence of skin in 정수리)

Question 21

Genotype for Klinefelter syndrome

Answer 21

47 XXY

Question 22

Genotype for Turner Syndrome

Answer 22

45 XO

Question 23

Aneuploidy (having missing or extra chromosomes) pathologies that are best diagnosed through ultrasound

Answer 23

Trisomy 18 (Edward's syndrome)
Trisomy 13 (Patau Syndrome)

Question 24

Females with the genotype 45 XO; short stature; WEBBED neck, “shield-like” chest, COARCATION of aorta and Renal malformations

Answer 24

Turner Syndrome

Question 25

Signs/Symptoms of Turner Syndrome

Answer 25

``` Short stature Webbed neck Broad "shield-like" chest Coarctation of Aorta (narrowing of a short section of aorta) horseshoe kidney ```

Question 26

Examples of Prenatal Diagnostic Testing and Screening

Answer 26

Chorionic Villus sampling Amniocentesis Multiple Marker Screening (cfDNA) Genetic/Carrier Screening

Question 27

When is Chorionic Villus Sampling done

Answer 27

10-14 weeks

Question 28

Limitation of Chorionic Villus Sampling

Answer 28

Can't test for open neural tube defects

Question 29

When is Amniocentesis performed?

Answer 29

>15 weeks

Question 30

(Chorionic Villus Sampling/Amniocentesis) can test for open neural tube defects

Answer 30

Amniocentesis

Question 31

Proportion of unaffected individuals with a negative result; "TRUE" negatives

Answer 31

Specificity

Question 32

Proportion of AFFECTED individuals with POSITIVE result; "TRUE" positives

Answer 32

Sensitivity

Question 33

What proteins does the "Quad screening" look for

Answer 33

AFP hCG DIA (Inhibin A) uE3 (estriol)

Question 34

What are the Quad Screening values for Down Syndrome (AFP, uE3, Inhibin and hCG)

Answer 34

Low AFP Low uE3 High hCG High Inhibin

Question 35

Serum protein marker; synthesized in the yolk sac, GI tract and liver of fetus; can indicate Multiple Gestations, Cystic Hygroma, Neural tube defects (Spina bifida, Anencephaly), Abdominal Wall and GI defects

Answer 35

AFP (Alpha-fetoprotein)

Question 36

What can cause an elevated AFP

Answer 36

``` Multiple gestations Spina bifida Anencephaly Abdomina Wall and GI defects Cystic Hygroma ```

Question 37

Serum protein marker; produced by synctiotrophoblasts; rapidly peaks around 8 weeks, then decreases

Answer 37

hCG (Human Chorionic Gonadotropin)

Question 38

Serum protein marker; produced by placenta from precursors from fetal adrenal glands and liver; steadily inc. throughout preganncy; low levels can indicate Smith-Lemli-Optiz syndrome and Ichthyosis

Answer 38

uE3 (Estriol)

Question 39

Low levels of uE3 can be indicative of what pathologies

Answer 39

Smith-Lemli-Opitz Syndrome | Ichthyosis (widespread and persistent thick, dry, "fish-scale" skin)

Question 40

Serum protein marker; produced by gonads, corpus luteum and placenta; inhibits FSH

Answer 40

Inhibin A

Question 41

Common conditions seen in Ashkenazi Jews

Answer 41

``` Tay Sacks Cystic Fibrosis Canavan disease Familial Dysautonomia Gaucher Disease ```

Question 42

Mutation seen in Cystic Fibrosis

Answer 42

delta F508

Question 43

Which Trinucleotide repeat is seen in Fragile X (elf looking kids)

Answer 43

CGG