Peds Genetics Flashcards
What are the 3 types of point mutations?
- Silent
- Nonsense (STOP)
- Missense (codes for another protein)
Autosomal Dominant Pattern
50% of getting disorder
Autosomal recessive Pattern
25% of getting disorder (if both parents are carriers)
When is Maternal Serum Screening take place?
2nd Trimester (15-20 weeks)
When is technically Advanced maternal age?
> 35 years old
Omphalocele
Birth defect in which an infant’s intestine or other abdominal organs are outside of the body because of a hole in the belly button (navel) area
Polyhydraminos
defined as >2L of amniotic fluid
- associated with GI abnormalities
ex. duodenal atresia and omphalocele
Duodenal atresia
the congenital absence or complete closure of a portion of the lumen of the duodenum. It causes increased levels of amniotic fluid during pregnancy (polyhydramnios)
- Bilious vomiting
- Double Bubble sign on Xray**
Oligohydraminos
Associated with:
-Renal problems (ex. Horseshoe Kidney)
What is the most important maternal blood sample
Alpha-fetoprotein (aFP)
Increased levels:
- Anencephaly
- Spina bifida
Decreased levels:
- Trisomy 21 (Down Syndrome)
- Trisomy 18 (Edwards Syndrome)
Clindodactyly
Mild birth defect where the middle bone of the 5th digit is wedge shaped
(associated with Down’s)
Trisomy 21
- Hypotonia**
- Brushfield eye spots
- Sandal toe
- Simian crease*
- AV canal
- Duodenal atresia
- HIrschsprung
- Hypothyroidism
- Atlantoaxial instability*
Trisomy 18 (Edwards Syndrome)
- Clenched hand with overlapping fingers
- Rocker bottom feet**
- Small jaw
Turner’s syndrome (XO)
- Webbed neck
- low hairline
- Peripheral lymphedema**
- Coarctation of the aorta**
- Ovarian dysgenesis-amenorrhea
What is the best kind of testing to look for DiGeorge Syndrome
FISH (Fluoresence in Situ Hybridization)
New born screening
1st: in hospital, 24 hours of life
2nd: Clinic, 5-14 days of life
PKU -Phenylketonuria
Increased levels of phenylalanine in the urine
MC amino acid disorder**
- Mousy odor*
- Blonde hair blue eyes
- Severe mental retardation
- Autism
- Seizures
What is the screening test for congenital hypothyroidism?
TSH will be HIGH
Congenital Hypothyroidism: Sx
Newborn symptoms:
- larger posterior fontanelle
- Prolonged jaundice
- Macroglossia
- hoarse cry
- umbilical hernia
Congenital Adrenal Hyperplasia (CAH)
Increased 17-OH Hydroxylase
- ambiguous genitalia
- classic salt wasting syndrome**
Genetic Imprinting -different disease based on which parent has missing allele
- Prader-Willi Syndrome (missing paternal allele)
2. Angelman Syndrome (missing maternal allele)
What is the best testing for Prader-Willi Syndrome or Angelman Syndrome?
FISH
Prader-Willi Syndrome
Deletion of 15q11-q13 - PATERNAL
- Severe hypotonia as an infant
- Obesity/Hyperphagia
- Small hands and feet
- Hypogonadism
- Intellectual disability
Angelman Syndrome
Deletion of 15q11-q13 - MATERNAL
- “happy puppet” Jerky ataxia
- Fair hair
- Seizures
- Uncontrollable bouts of laughter
- Severe intellectual disability
