genetics Flashcards
amplification of a sequence of three nucleotides
Increasing severity of clinical disease in each successive generation (anticipation)
trinucleotide-repeat mutation
huntington’s disease
myotonic dystrophy
friedreich ataxia
fragile x syndrome
mendelian disorder that has incomplete penetrancewith variable expressivity
autosomal dominant disorders
largest category in mendelian disorder
mostly inborn errors of metabolism
usually seen in consanguinity
autosomal recessive disorders
all enzymatic mutation are autosomal recessive EXCEPT
acute intermittent porphyria which is a autosomal dominant
all mucopolysaccharide are autosomal recessive EXCEPT
Hunter syndrome which is a X linked recessive
all glycogen storage disease are autosomal recessive EXCEPT
Faber
what are the x linked recessive disorder memorize
Brutons agammaglobulinemia wiskott aldrich fabrys G6PD ocular albinism lesch nyhan duchennes huntesr hemophilia
how many of the offsprings of mother with a mitochondrial inheritance dx manifests the disease
ALL
what is the inherited defect in an extra cellular glycoprotein found in Marfan
fibrillin-1
defect in the synthesis of fibrillar collagen
Ehler’s danlos
most common type of collagen defect found in Ehler’s danlos
type 3 hyper mobility
what is deficient in tay-sachs disease
hexosaminidase alpha subunit deficiency
predominant cns and retinal involvement
what accumulates in tay-sachs
GM2 ganglioside -onion skin lesion, whorled configuration
chery red spot in macula
what is deficient in niemann-pick disease
spengomyelinase
severe infantile form with extensive neurologic involvement is what type of niemann-pick?
type A
organomegly with no cns involvement is what type of niemann pick?
type B
lysosomal storage dx with zebra bodies
niemann pick
both niemann pick and tay sachs have cherry red spot in macula with mental retardation. what is the difference?
np has hepatosplenomegaly
what accumulates in np
sphingomyelin
most common lysosomal storage disease
gaucher -tissue paper appearance
gaucher cells when accumulates in the brain
Virchow robin spaces
deficiency in gaucher
glucocerebrosidase
accumulation of glucocerebrosites
balloon cells are found in?
mucopolysaccharidoses
type of glycogen storage disease involving the heart
type 2 Pompe alpha 1,4 glucosidase
type of glycogen storage disease with glycogen debranching enzyme deficiency
type 3 Cori
type of glycogen storage disease with hepatic glycogen phosphorylase enzyme deficiency with hypoglycemia and cirrhosis
type 6 Hers disease
type of glycogen storage disease with branching enzyme deficiency
Type 4 andersen, infantile hypotonia
type of glycogen storage disease muscle glycogen phosphorylase enzyme deficiency
type 5 McArdles muscle cramps and weakness on exercise
glycogen storage disease type 1
von gierkes. glucose 6 phosphatase def. severe hypoglycemia
lack of homogenistic oxidase leading to black urine
alkaptonuria
enzyme that converts homogenistic acid to methyacetoacetic acid
homogenistic oxidase
blue black pigments in nose, ears, cheeks
deposits also in articular cartilages
ochronosis in alkaptonuria
problem in tyrosine metabolism
alkaptonuria
how many chromosomes in normal karyotype
46
most common chromosomal syndrome
downs trisomy 21
trisomy 21 simian crease mr endocardial cushion defect duodenal atresia hirschprnug all alzheimer
downs
expected result in quadruple screen for downs?
utz finding
increase bhcg and inhibin a
decrease afp, estriol
increased nuchal translucency
trisomy 18
clenched hands with overlapping fingers micrognathia rocker bottom feet vsd early death
edwards
trisomy 13 cleo lip palate polydactyl holoprocencephaly rocker bottom feet vsd
patau
catch 22
digeorge syndrome
cardiac defect abnormal facies thymic aplasia cleft palate hypocalcemia 22q11.2 deletion
47 Xxy
male hypogonadism
testicilar atrophy
enuochoid body shape
klinefelter
no barr body streak ovary shield chest webbed neck coarctation of aorta
xo
turner
micro deletion of long arm of chromosome 7 elfin facies mr hypercalcemia well developed verbal skills extreme friendliness with strangers
williams
large mandible,ears, testis
2nd most common cause of mr
Fragile X syndrome
paternal chromosome 15
obesity hyperhagia
praderwilli
maternal chromosome 15
marionette
happy puppet
Angelman
mutation in single genes with a large defect
mendelian
