Genetics Flashcards by Sam Biniazan

Chorionic villus sampling

12 weeks

How well did you know this?

Not at all

Perfectly

Amniocentesis

16 weeks

How well did you know this?

Not at all

Perfectly

Genetic disorders caused by mutation in one gene

Monogenic inheritance

How well did you know this?

Not at all

Perfectly

Genetic disorders caused by mutation in multiple genes

Multifactorial inheritance

How well did you know this?

Not at all

Perfectly

Genetic disorders caused by combination of gene mutations and environmental factors

Epigenetics

How well did you know this?

Not at all

Perfectly

Chances of having a child with X-linked recessive disorder if mother is carrier

25% disease

25% carriers
50% normal

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

Test necessary for imprinting disorders

(ie Prader-willi, angelman, beckwith-wiedeman, Russell-silver)

Methylation test

How well did you know this?

Not at all

Perfectly

Short stature
Broad webbed neck
Bicuspid valve
Coarctation of aorta
Hypothyroidism
Gonadal dysgenesis
diffusely enlarged nodular thyroid gland

Turner syndrome

How well did you know this?

Not at all

Perfectly

Screening for most common co-morbidities with Turner

ECHO
4 extremity BP
Renal US
TSH
Growth velocity

How well did you know this?

Not at all

Perfectly

Most common chromosomal defect discovered in spontaneous abortions

Turner syndrome

How well did you know this?

Not at all

Perfectly

Definitive diagnostic test for Turner syndrome

Karyotype

How well did you know this?

Not at all

Perfectly

Pectus excavatum
Webbed neck
Low set ears
Pulmonary stenosis
Normal karyotype
Bleeding diatheses

Noonan syndrome

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

Mutation in Marfan

Chromosome 15
Fibrillin gene

How well did you know this?

Not at all

Perfectly

Asymmetric pectus carinatum

Marfan

How well did you know this?

Not at all

Perfectly

Downward displaced eyes
Low IQ
Thrombosis

Homocystinuria

How well did you know this?

Not at all

Perfectly

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

How well did you know this?

Not at all

Perfectly

Most common abnormality seen in Down syndrome

Hypotonia

How well did you know this?

Not at all

Perfectly

Low set ears
Epicanthal folds
Upslanted palpebral fissures
Brushfield spots (speckled iris)
Single transverse palmar creases

Down syndrome

How well did you know this?

Not at all

Perfectly

Complications of Down syndrome

Leukemia
Duodenal atresia
Endocardial cushion defect
Atlantoaxial instability

How well did you know this?

Not at all

Perfectly

Diagnostic evaluation for Down syndrome

FISH

How well did you know this?

Not at all

Perfectly

Clenched fist
Rocker bottom feet
Overlapping fingers
Hypoplastic nails
Prominent occiput,Microcephaly
Horseshoe kidneys

Trisomy 18 (Edward syndrome)

How well did you know this?

Not at all

Perfectly

Bad Brain
Low set ears
Polydactyly
Bicornuate uterus
Cleft lip/palate
Cystic kidneys
Rocker bottom feet
Cutis aplasia (pathognomonic)

Trisomy 13

How well did you know this?

Not at all

Perfectly

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