Neurogenetics Flashcards
autosomal dystonia 1
Most common DYT1 mutation is in Ashkenazi Jews GAG deletion most common
Pantothenate kinase Deficiency
Gene=PKAN Brain Iron Accumulation
CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy)
NOTCH3 Stroke-like episodes before age 60, cognitive disturbance, behavioral abnormalities, migraine with aura T2 white matter abnormalities
A newborn has weakness, hypotonia, absent reflexes, and tongue fasciculations.
SMA which in some cases is due to a gene conversion event of SMNC to SMNT
Which of the following is the best way to establish whether the child is affected at birth with DMD?
Creatine phosphokinase levels will be elevated at birth for a boy with Duchenne muscular dystrophy, well before muscle weakness will be apparent. Genetic testing could be done, but the family mutation is not known, so a negative test will be difficult to interpret, and should not be necessary. Physical exam will be normal at this age and muscle biopsy, besides being invasive, will likely miss pathology this early in life
Brain malformations- Lissencephaly
- Lissencephaly is characterized by a smooth brain surface without gyri.
- Polymicrogyria is the occurrence of a large number of small gyri;
- pachygyria is the occurrence of a small number of large gyri;
- schizencephaly is the occurrence of a cleft in the brain.
Facio-scapulo-humeral muscular dystrophy on what chromosome?
FSH dystrophy is due to deletions of a repeat region in the 4q subtelomer
Notch3 gene mutations cause which of the following neurologic complications
Answer: E. Notch3 mutations are associated with CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy).
Myasthenia gravis affects which of the following components of the neuromuscular system
Neuromuscular junction
A massively elevated CK (creatine kinase) level is found in a 4-year-old boy with progressively worsening gross motor delay. This finding is typical for which of the following neuromuscular disorders?
Duchenne and Becker dystrophies are associated with major CPK
elevations. The other disorders either do not cause elevation, or the elevation is typically
minor.
A 7-year-old with NF1 develops an acute left hemiparesis. Which of the following clinical findings is the most likely cause of acute stroke in NF1?
Individuals with NF1 are at increased risk of internal carotid occlusion and associated moyamoya syndrome.
von Hippel-Lindau syndrome during pregnancy
Women with VHL should be followed during pregnancy for development of pheochromocytoma.
A 50 year old man presents with pain and is found to have multiple schwannomas. A brain MRI
shows no evidence for vestibular schwannoma. Which pair of genes would be appropriate to test
to determine whether he might have schwannomatosis?
SMARCB1 and LZTR1 are both associated with schwannomatosis.
Schwannomas can be found in NF2 patients, but usually in association with vestibular
schwannomas and other features. TSC2 is associated with tuberous sclerosis complex,
not schwannomatosis.
Parkinson Disease
Having one N370S glucocerebrosidase allele has been indicated as a
risk factor for Parkinson disease. None of the other conditions is associated with carrier
status for glucocerebrosidase.
cerebellar and retinal hemangioblastoma
The presence of cerebellar and retinal hemangioblastoma is indicative
of von Hippel-Lindau syndrome, which is also associated with endolymphatic sac tumor,
that can cause hearing loss. A brainstem hemangioblastoma is not likely to cause hearing
loss, though it could occur in VHL.
