Genetics Flashcards
Chorionic villus sampling
12 weeks
Amniocentesis
16 weeks
Genetic disorders caused by mutation in one gene
Monogenic inheritance
Genetic disorders caused by mutation in multiple genes
Multifactorial inheritance
Genetic disorders caused by combination of gene mutations and environmental factors
Epigenetics
Chances of having a child with X-linked recessive disorder if mother is carrier
25% disease
25% carriers
50% normal
Variable expressivity
Possible reduced penetrate
High risk for spontaneous mutation with no prior family history
Only way a disease can be transmitted from father to son
Autosomal dominant
Test necessary for imprinting disorders
(ie Prader-willi, angelman, beckwith-wiedeman, Russell-silver)
Methylation test
Short stature
Broad webbed neck
Bicuspid valve
Coarctation of aorta
Hypothyroidism
Gonadal dysgenesis
diffusely enlarged nodular thyroid gland
Turner syndrome
Screening for most common co-morbidities with Turner
ECHO
4 extremity BP
Renal US
TSH
Growth velocity
Most common chromosomal defect discovered in spontaneous abortions
Turner syndrome
Definitive diagnostic test for Turner syndrome
Karyotype
Pectus excavatum
Webbed neck
Low set ears
Pulmonary stenosis
Normal karyotype
Bleeding diatheses
Noonan syndrome
Major criteria for Marfan
(Must meet more than 2)
Progressive dilatation or dissection or ascending aorta
Lumbosacral Dural ecstasia
Ectopia lentis (upward slanting eyes)
Four skeletal manifestations
Family or generic history
Mutation in Marfan
Chromosome 15
Fibrillin gene
Asymmetric pectus carinatum
Marfan
Downward displaced eyes
Low IQ
Thrombosis
Homocystinuria
Autosomal recessive
Cholesterol synthesis defect (low total cholesterol)
SGA, intellectual disability
Syndactyly of 2nd and 3rd toes
Smith-Lemli-Opitz Syndrome (SLOS)
Deficiency of 7-dehydrocholestorol
Tx: cholesterol supplements
Poor prognosis - most dye in early childhood
Most common abnormality seen in Down syndrome
Hypotonia
Low set ears
Epicanthal folds
Upslanted palpebral fissures
Brushfield spots (speckled iris)
Single transverse palmar creases
Down syndrome
Complications of Down syndrome
Leukemia
Duodenal atresia
Endocardial cushion defect
Atlantoaxial instability
Diagnostic evaluation for Down syndrome
FISH
Clenched fist
Rocker bottom feet
Overlapping fingers
Hypoplastic nails
Prominent occiput,Microcephaly
Horseshoe kidneys
Trisomy 18 (Edward syndrome)
Bad Brain
Low set ears
Polydactyly
Bicornuate uterus
Cleft lip/palate
Cystic kidneys
Rocker bottom feet
Cutis aplasia (pathognomonic)
Trisomy 13
Tall
Small testes
Cryptorchidism
Gynecomastia
Klinefelter syndrome
Diagnostic test and management for Klinefelter syndrome
Chromosome analysis
Testosterone supplementation
Central hypogonadotropic hypogonadism
Anosmia
Tall/thin
Small testes/cryptorchidism
Cleft lip/palate
Mirror movements
Kallman syndrome
Mutation of the ANOS1 gene at Xp22.3
Neonatal hypotonia
FTT as infant
Voracious appetite
Obesity
Intellectual disability
OCD
small hands/feet
Almond-shaped eyes
Prader-will syndrome
Diagnostic test and management for Prader-Willi syndrome
Methylation test
15q11-13 deletion
Growth hormone
Nutritional management
Big smile
Intellectual disability
Ataxia/seizures
Laughter/excitability
Feeding issues
Angelman syndrome
Diagnostic test for Angelman syndrome
Methylation test
15q11-13 deletion
Macroglossia
Macrosomia
Hypoglycemia
Hemihypertrophy
Renal anomolies
Hypospadias
Omphalocele
Abdominal mass
Beckwith wiedeman syndrome
Most common imprinting disorder
Beckwith wiedeman syndrome
Diagnostic test and management for beckwith wiedeman syndrome
Methylation test
11p15.5 alteration
Predisposed to malignancy
AFP every 6-12 weeks until 4yo
Abdominal US every 3 mo until 8yo
Tumors children with beckwith wiedeman syndrome are at risk for
Rahbdomyosarcoma
Wilm’s (nephroblastoma)
Hepatoblastoma
Neuroblastoma
Elfin facies
Prominent philtrum
Big lips/mouth
Cocktail party personality
Stellate irises
Williams syndrome
Complications of Williams syndrome
Hypercalcemia
Supravalvular aortic stenosis
Conotruncal defects (Tetrology of Fallot)
Abnormal Davies
Thymic aplasia/immunodeficiency
Cleft palate/cryptorchidism
Hypoparathyroidism
DiGeorge syndrome
22q11 deletion syndrome
Velocardialfacial syndrome
Diagnostic test for DiGeorge syndrome
Chromosomal microarray (CMA)
Coloboma/cognitive deficits
Heart defects
Atresia/stenosis (choanal)
Retarded growth/development
GU abnormalities
Ear anomalies (hearing loss)
CHARGE syndrome
Autosomal dominant in CHD7 gene
Broad thumb
Cryptorchidism
Rubinstein-Taybi syndrome
Bilateral coronal crani pay ptosis
Significant proptosis
Wide spaced eyes
Wide thumbs
Pfeiffer syndrome
Similar head to Pfeiffer
No hand issues
Crouzon syndrome
Craniosynostosis
Mitten hands +/- feet
Apert syndrome
Face elongated
Repeat CGG
Autism, ADHD
Giant genitals (macroorchidism)
IQ Lower
Large hands/feet
Ears big
X-linked dominant
Fragile X syndrome
Diagnostic test for Fragile X
DNA testing
Triplet CGG expansion on FMR1 gene
Most common single-gene cause of Autism spectrum disorder
Fragile X
Most common cause of X-linked intellectual disability
Fragile X
Regression of developmental milestones
Autistic-like behavior
Wringing hands
X-linked dominant
Only on Females (males don’t survive pregnancy)
Rhett syndrome
Most common preventable teratogenic cause of intellectual disability
Fetal alcohol syndrome
Flat Philtrum
Thin vermilion border of upper lip
Midface hypoplasia
Short palpebral fissures
Deficient brain growth
Growth retardation
VSD
Fetal alcohol syndrome
Low birth weight/IUGR
Higher miscarriage rates
Placental abruption
Placenta previa
Prematurity
Cleft lip/palate
Tobacco exposure
Complications of prenatal tobacco exposure
Asthma
Otitis media
Wheezing
SIDS
Abnormal neurobehavior
IUGR
Broad nose bridge
Fingernail hypoplasia
Neural tube defect
Anticonvulsants
Valproic acid
Carbamazepine
Cleft palate
Postnatal bleeding
Microcephaly
Hypoplastic nails
Hypertelorism
Short, upturned nose
AED
Fetal hydantoin syndrome
(phenytoin)
vertebral defects/tethered cord
Anal atresia
Cardiac defects
TE fistula
Renal abnormalities
Limb abnormalities
Single umbilical artery
VACTER-L
Parallelogram head shape
Position plagiocephaly
Ipsilateral ear displacement
Ipsilateral frontal bossing
Normal sutures on CT Head
Most likely from lying on back
Will self-improve
Trapezoidal head shape
Unilateral lamboid synostosis
Ipsilateral ear displacement
Contralateral frontal bossing
Dolichocephaly
Scaphocephaly
Saggital synostosis
Brachycephaly
(Crouzon, Pfeiffer syndrome)
Bilateral coronal sutures
Trigonocephaly
Metopic sutures
Cloverleaf skull
(Apert)
Multiple suture synostosis
Cleft palate
Micrognathia
Glossoptosis (tongue sticks out)
Extremity/vertebral anomalies
Language/developmental delay
Pierre Robin syndrome
Complication of Pierre Robin
Cor pulmonale sue to upper airway obstruction caused by glossoptosis
Renal agenesis
Hypoplastic lungs
Limb malformations
Oligohydramnios sequence
(Potter sybdrome)
Complication of Potter syndrome
Die of pulmonary complications
Triangle face
Growth retardation
Russell Silver syndrome
Lack of abdominal muscle development
Bladder outlet obstruction
Oligohydramnios
Pulmonary hypoplasia
Undescended testes
Prune belly syndrome
Conductive hearing loss
Small jaw
Ear abnormalities
Lower eyelid abnormalities
Midface and mandibular dysmorphology
Treacher Collins syndrome
(Mandibulofacial dystosis)
Macrocephaly
Frontal bossing
Genu Verum (bowlegs)
Short extremities (rhizomelic shortening)
Achondroplasia
Autosomal dominant
Complications of achondroplasia
Cervicomedullary junction compression (most common cause of death in children) due to small foremen magnum
Sleep apnea
Otitis
Hearing loss
IUGR
Limb anomalies (short fingers, absent UE)
Synophrys
Arched eyebrows
Small upturned nose
Microcephaly
Hirsutism
Oligodactyly
Cornelia de Lange
Paucity of intrahepatic bile ducts (confirmed with liver biopsy)
Butterfly vertebrae
Cholestatic jaundice
Alagille syndrome
Clinical criteria for neurofibromatosis 1
(Von recklinghausen disease, ch 17)
> 6 cafe au lait spots (> 5mm in diameter in prepubertal and > 15 mm in post pubertal)
Axillary or inguinal freckles
> 2 typical neurofibromas or > 1 plexiform neurofibroma
Optic nerve glioma
> 2 iris hamartomas (lisch nodules)
Sphenoid dysplasia
Tibial pseudoarthrosis
1st degree relative with NF1
Congenital sensorineural hearing loss
Heterochromia
Hair hypopigmentation (white forelock)
Displacement of medial canthi
Cutaneous depigmentation
Waardenburg syndrome
Wilms tumor
Aniridia
GU abnormalities
Reduced intellectual abilities
WAGR
Multilocular cystic mass in nuchal region
Aneuoloidy
Cystic hygroma
Benign proliferating bone disease
Infants
Extreme irritability
Fever
Soft tissue swelling
Cortical hyperostosis
Caffey disease
Keyhole like or notch like defect affecting iris, ciliary body, retina, and/or optic nerve
Microphthalmia
Nystagmus
Coloboma
Sudden death with growth hormone administration
Prader-Willi syndrome
