genetics Flashcards
GA for chorionic villus sampling
12 weeks
GA for amniocentesis
16 weeks
XL dominant conditions
hypophosphatemic rickets
pseudohypoparathyroidism
Aicardi syndrome
Alport syndrome
penetrance
some people exhibit the phenotype of the gene and some don’t
expression
range of phenotypes for people with same genetic condition
when to order FISH testing
looking for contiguous gene deletions or duplications - copy number variants
short stature, webbed neck, L-sided congenital cardiac defects
45XO, Turner syndrome
higher likelihood of diabetes or IBD
elevated FSH
karyotype, FISH for mosaicism
webbed neck, downslanting eyes, triangular facies, hearing loss, pectus carinatum/excavatum, cryptorchidism, MR, pulmonary stenosis
Noonan syndrome
inheritance/genetics of Marfan
AD
fibrillin gene on Chr 15
asymmetric pectus carinatum
Marfan
translocation and risk of transmission
15% if partial, 100% if full
higher if mother is carrier of translocation
increased risk of which things with T21
leukemia
duodenal atresia
AV canal defects (NW axis on EKG)
atlantoaxial instability
rocker bottom feet, overlapping fingers, microcephaly, horseshoe kidneys
T18
polydactyly, cutis aplasia, cleft lip/palate, cystic kidneys, abnormal female GU
T13
tall, infertile teen, small testes, normal intelligence but social awkwardness, gynecomastia
Klinefelter (47XXY)
tx: testosterone supplementation
neonatal hypotonia and FTT –> obesity, small testicles, ID
Prader Willi
15q11
methylation test
frequent laughter, ataxia, speech impairment, spasticity/jerky movements
Angelman
15q11
methylation test
omphalocele, macroglossia, hypoglycemia, hemihypertrophy
Beckwith Wiedemann
dx methylation test
malignancy risk with Beckwith Wiedemann
embryonal tumors-
rhabdomyosarcoma
Wilms
neuroblastoma
screening needed in Beckwith Wiedemann
AFP q 6 weeks
abdominal US every 3 months
elfin face, wide spaced teeth, very friendly, hypercalcemia, supravalvular aortic stenosis
Williams syndrome
chr 7
genetics/inheritance of DiGeorge
AD inheritance
22q11
dx with microarray
genetics/inheritance of CHARGE
AD (spontaneous) mutations in CHD7 gene
broad thumb, cryptorchidism
Rubenstein Taybi
broad thumbs and toes, widely spaced prominent eyes
Pfeiffer syndrome
male with ID, long narrow face, protruding ears, high arched palate, macroorchidism
Fragile X
CCG expansion
need fragile X testing
flat philtrum, thin vermilion border, midface hypoplasia
FAS
risks with maternal smoking
LBW miscarriage placental abruption/previa cleft lip/palate respiratory prolems SIDS deficits in mental development, language, ADHD, IQ
neural tube deficits and facial deformities
valproic acid or carbamazepine exposure
finger stiffness, nail hypoplasia, cardiac anomalies
phenytoin
Potter syndrome
renal agenesis –>
facies
hypoplastic lungs
limb malformations
“glove like” excess skin on hands, fetal membranes with yellowish nodules
triangle face, growth retardation
Russell Silver
cause of prune belly
bladder outlet obstruction –> oligohydramnios
undescended testes
facial abnormalities, conductive hearing loss, normal IQ
Treacher Collins
AD inheritance
complications of achondroplasia
lumbar lordosis
small foramen magna –> nerve root compression
sleep apnea
increased risk of SIDS
