Genetics Flashcards
Mutation in ras/mitogen kinase signaling gene, seen in what disease?
Noonan
Describe characteristics of infantile cortical hyperostosis (Caffey disease)
on physical exam there are hard swllings fixed to bone, movement of bone is limited
xrays show gradual cortical thickening, periosteal bone formation around diaphysis. most frequently affected locations are ascending ramus and angle of mandible
most cases sporadic
tibia is affected in familial cases
Describe some features of Smith-Lemli-Opitz
associated with low unconjugated estriol
AR
microcephaly, hypospadias, heart murmur, wide-spaced eyes, and polydactyly of the left foot.
pyloric stenosis
renal dysgenesis
Features of OTCD deficiency
elevated plasma alanine and glutamine levels
elevated urine orotic acid levels
plasma citrulline, arginine, and BUN levels decreased
Physical Features of Smith-Lemli- Opitz?
micrognathia, flattened nose, cleft palate
hypotonia, pan systoli murmur, axial polydactly
renal agensis
defect in 7-Dehydrocholesterol reductase
In what disorder do you see triphalangeal thumbs?
Diamond-Blackfan Syndrome
In what disorders do you see cystic lymphangiomas?
Trisomy 13, 18, 21, and Noonan and Turner
What is Hay-Wills Syndrome?
ectodermal, cleft lip palate syndrome
you see skin peeling, congenital strands of tissue around eyelids, lacrimal duct atresia, external ear malformation, hypospadiasis
What is most pressing issue in neonatal period of those with achondroplasia?
evaluation of craniocervical junction, as many as 8% of infants may die due to compression of spinal cord due to cervical narrowing.
What is Potter’s Face
Potter’s face refers to a parrot-beak nose, micrognathia, low-set ears, flattened nose, widely spread eyes, and the presence of skin folds from the edge of the eye
What is triad of Pierre Robin Sequence
Micrognathia, posterior displacement of tongue, and upper airway obstruction
What is Wardenberg Syndrome?
a rare genetic disorder characterized by deafness, pigmentation anomalies (hair and eyes), and minor deficits in anatomical structures that evolve from the neural crest.
It is now known that selective disruption during myogenesis, especially in the mutation of gene PAX3, is the cause of Waardenburg syndrome
What would prenatal imaging show for Turner’s Syndrome?
ultrasound reveals cystic hygroma, increased nuchal translucency, coarctation of the aorta/left-sided cardiac anomalies, brachycephaly, horseshoe kidney, polyhydramnios, oligohydramnios, or non-immune fetal hydrops.
3 different ways BWS inherited
loss of methylation maternal chromosome 11 (50%)
parental disomy (20%)
gain of methylation (5%)
VACTERL association
Vertebral Anomalies
Anal Atresia
Cardiac (VSD > TOF > Coarc)
TE fistula
Renal anomaly
Limb dysplasia
Clinical features Townes Brock Syndrome
imperforate anus, dysplastic ears, thumb anomalies
In what different genetic conditions do you see mutations in FGF 2?
Apert and Crouzon syndrome
Differences between Apert and Crouzon
Apert greater risk of mental deficiency
Apert midface hypoplasia, crouzon maxillary hypoplasia
Apert irregular craniosynostosis
Crouzon, premature craniosynostosis
Crouzon, curved beaked nose
Apert syndactyl and broad distal phalynx, thumbs and toes
Apert Cardiac defects
List some features of Sturge-Weber Syndrome?
Port wine stain
tramline intracortical calcifications
glaucoma
seizures
macrocephaly
cardiac rhadbomyomas
DNA Testing mnemonic
SNW DRP
Trisomies result from an extra copy of which parent?
mother
Holt Oram syndrome
AD
Cardiac defects (ASD)
upper limb defects
absent or hypoplastic thumbs
hypertleroism
Angeleman
microdeletion from mother
wide spaced mouth, large teeth
puppet like gait, neuro abnormalities
Prader Wili
deletion from paternal origin
small hands feet
almond shaped eyes
hypogenitalia
obesity
Rubenstein-Taybi
cardiac defects, broad thumbs, toes,
hypoplastic maxilla
hirsutism
downward slanint palpebral fissures
X-linked recessive. Classic findings include brittle, light-colored (white/gray) hair, thin/absent eyebrows, hyperelastic skin, full cheeks, and a high-arched palate
Menkes disease
(x linked recessive)
copper transport issue
What is incidence of minor congenital anomalies vs major congenital anomalies.
20% minor
3% major
What is a cis-acting regulatory element?
regions of non-coding DNA that regulate gene transcription
promoters, enhancers, repressors are examples
High forehead, large fontanelles, hypertelorism, and micrognathia.
with increased plasma VLFCAs and absent peroxisomes within the cells.
Zewellger Syndrome
