Genetic Diseases III Flashcards
trinucleotide repeat expansion diseases
fragile X syndrome
huntington disease
how is fragile X syndrome spread
x linked dominatent
how is huntinton disease spread
autosomal dominant
anticipation
genes rendered abnormal by amplification o fCG-rich units
in diseases with anticipation they get better or worse from generation to generation?
worse
trinucleotide repeat expation
have an increased number of a repeating series of 3 nucleotides
how are TREs impacted from 1 generation to the next
number of repeats increases from 1 generation to the next
fragile x syndrome
leading cause of inheritied mental impairment and leading known single-gene cause of autism
what mutation is fragile X syndrome associated with
increased CGG repeats in the FMR1 gene
intermediate range
range of repeats that is normally stable
premutation range
always changes in size
expansion from pre to full mutation occurs thorugh what
female meiosis
symptoms of fragile X syndrome
mental retardation
big ears
big upper jaw
big testicles
who has milder features of fragile X syndrome?
females
where is huntington disease gene
chromsomes 4
what is the mutation that causes HD
expansion of CAG trinucleotide repeats on HD gene
what is the mean age of onset for HD
35-44 years
what is the medial survival time of hD
15-18 years
early stages of HD
jerky movements
difficulty in mental palnning
depressed
secondary stage of HD
chorea beocme more prominant
worsening dysarthria and dysphagia
late stage of HD
behavior problems are lessened
severe motor disability
individual may become totally dependent, mute, incontinent
what is edwards syndrome caused by
presence of an extra chromosome 18
symptoms of edwards syndrome
rocker bottom feet
low set ears
congetical heart defect
prominent occiput
what causes patau syndrome
trisomy 13
symptoms of patau syndrome
polydactyly
cleft lip
microcephaly
rocker bottom feet
trinucleotide repeat expansion
have an increased number of a repeating series of 3 nucleotides
fragile x syndrome
leading cause of inherited mental impairment and leading known single-gene cause of autism
where is huntington disease gene
chromosome 4
symptoms of patau syndrome
polydactyly
cleft lip
microcephaly
rocker bottom feet
what is turner syndrome caused by
monosome X
phenotype of turner syndrome
female
prenatal features of turnur syndrome
common to have early miscarriages
cystic hygroma
clinical features of turner syndrome at birth
webbed neck
puffy hands and feet
low set rotated ears
affects turner syndrome has on heart
left side cogential heart disease
bicuspid aortic valve
characteristics of adults with turner syndrome
short sexual infantilism webbed neck broad chest short 4th metacarpal
turner syndrome during puberty
amenorrhea
failure to develop secondary sexual characteristics
streak ovaries
when should you be considering turner syndrome
failure to thrive and short stature
klinefelter syndrome
XXY
characteristics of adult people with klinfelter
taller long arms and legs gynecomatia hypogonadism learning disability, social immaturity
what do klinfelter have increased risk of
breast cancer
can males with klinefelter have children
no
genetic imprinting
genes and chromosomes sometimes differ whether they are acquired form om or dad
paternal deletion of 15q11 causes
prader willi
maternal deletion of 15q11 causes
angelman syndrome
what do people with prader willi look like
truncal obestiy
hypogonadism
small hands
what do people with angelman look like
wide stance
arm position
spasticity
general description of angelman
severely retarded, microcephaly and huge jaw
jerky, puppet like movements and laugh a lot
