multifactorial inheritance Flashcards
1
Q
MCC Of major anomalies in infants is due to what
A
multifactorial inheritance
2
Q
what is the threshold of a disease
A
amt of factors/symptoms you need of a disease before you are affected
3
Q
what causes cleft lip and palate
A
genetics and environment
4
Q
what is the 4th MC congenital disorder
A
cleft lip and palate
5
Q
how do we treat cleft lip and palate
A
we use a team approach of a bunch of different specialists
6
Q
what is cleft lip/palate
A
when frontonasal processes of face and lateral maxillary prominences do not unite at 3-4 weeks of development
7
Q
what are midline facial clefts from
A
deficient frontonasal development usually induced by the brain
8
Q
what are midline facial clefts usually associated with
A
holoprosencephaly (no 2 hemispheres in brain)
9
Q
what is the most common cleftlip/palate disorder
A
unilateral cleft lip (80%)
10
Q
what is classic cleft palate
A
V shaped palate
11
Q
what is submucosal cleft palate
A
hard palate shelves do not merge together, but soft tissue forms
12
Q
what else is common in someone with submucosal cleft palate
A
bifid or double uvula
13
Q
where is a U shaped cleft palate common in
A
Pierre robin malformation sequence
14
Q
what is a U shaped cleft is due to
A
obstruction by the tongue
15
Q
what are the MC chromosome anomalies associated with CL/CP
A
trisomy 13 and 18
16
Q
inheritance pattern of van der woude synd
A
autosomal dominant
17
Q
is van der woude synd congenital
A
yes
18
Q
mutations in IRF6 are in what synd
A
van der woude synd
19
Q
what occurs in van der woude synd
A
they either have cleft lip OR cleft palate
20
Q
inheritance pattern for stickler syndrome
A
autosomal dominant
21
Q
what type of disorder is stickler syndrome
A
CT disorder
22
Q
clinical manifestations of stickler syndrome
A
myopia, cataracts, retinal detachment, hearing loss, skeletal probs and arthririts, underdeveloped midface, cleft palate
23
Q
myopia?
A
nearsightedness
24
Q
micrognathia? what can it cause?
A
small jaw that can cause airway obstruction bc the tongue is too big
25
mutations in COL2A1 are in what
COL2A1
26
what type of cleft palate do ppl with 22q11.2 deletion syndrome have
submucosal or classic CP
27
deletions in 22q11.2 deletion syndrome are detected by what
chromosome analysis, FISH, or microarray
28
inheritance pattern for 22q11.2 deletion syndrome
autosomal dominant
29
recurrence risk for someone with 22q, van der woude, and sticker are what
50% bc it's autosomal dominant
30
are most cleft lip/palate syndromic or nonsyndromic
nonsyndromic 70%
| syndromic 30%
31
what does the cause of nonsyndromic cleft L/P depend on
number of family members affected and the type and severity of the cleft
32
environmental causes of cleft lip and/or cleft palate
amniotic band sequence, alcohol, anticonvolusants, methotrexate, maternal tobacco
33
what are anticonvolusants
antiseizure drugs
34
what is methotrexate
drug used to treat cancer
35
cleft lip and/or cleft palate is more common in males or females
males
36
cleft palate alone is more common in maes or females
females
37
why do sex diff. occur in cleft L/P
unknown; maybe testosterone or gene dosages on the sex chromosomes
38
is pyloric stenosis more common in boys or girls
boys by a 5:1 ratio bc the genetic threshold is lower
39
if there is a gender difference in a multifactorial syndrome, who is the recurrence risk greatest for?
if the less affected sex (one with lowest threshold) has a child the opposite gender
40
who is the recurrence risk highest for in someone with pyloric stenosis
affected female has a son
41
who is the recurrence risk lowest for in someone with pyloric stenosis
affected father has a daughter
42
when is the neural tube formed
24-28 days
43
____% of pregnancies are unplanned; ____% for teens
50,80
44
how do we treat neural tube defects
surgery within 24 hrs of birth
45
what are the 3 neural tube defects? which is most common?
spina bifida (MC), anencephaly, and encephalocele
46
spina bifida?
when backbone and spinal canal dont form properly during fetal development
47
meningomyocele?
protrusion of meninges and spinal cord through the backbone
48
meningocele?
protrusion of meninges through the backbone
49
types of spina bifida?
oculta/closed, meninogmyocele, or meningocele
50
what is the degree of impairment related to in spina bifida oculta
location of the defect; higher the opening, the greater the impairment
51
what kinds of disabilities do ppl with spina bifida have?
paralysis of lower extremities, bowel or bladder function control, hydrocephalus
52
intelligence of ppl with spina bifida?
usually normal (70%), but some have ID
53
anal wink?
test done to see if someone with spina bifida has bowel/bladder function
54
hydrocephalus?
excessive fluid on brain
55
encephalocele?
part of skull is not formed correctly so part of brain is on outside of skull
56
what does the effect of encephalocele depend on?
size... 30% mortality rate
57
anencephaly?
brain and skull are not properly formed so most die. if they survive they usually die shortly after birth
58
besides surgery within 24 hours of birth for spina bifida, how can we treat it?
in utero, but long term effects are unknown
59
who do NTD usually occur in
95% in families with no prior hx of NTD
60
cause of NTD?
multifactorial: genetics and environment
61
NTD risk factors?
seizure meds, insulin dependent diabetes, maternal obesity, prolonged inc. maternal temp, celiac or malabsorption syndromes, gastric bypass
62
pyloric stenosis?
overgrowth of tissue in the pyloric region of the stomach so babies spit up food
63
NTD are most common in ppl with what ethnic background
hispanic women of mexican origin
64
antiepileptic drugs during pregnancy may increase risk for what?
congenital heart diseases, clefting, NTD
65
how should fevers be treated during pregnancy
tylenol
66
hyperthermia during pregnancy increases risk for what
NTD, ASD, and hypoplastic left heart
67
methylenetetrafolate reductidase is an enzyme used for what
folate metabolism
68
which allele do 10-20% of the US population have 2 copies of: C677T or A1298C?
C677T
69
is having 2 mutations in MTHFR harmful?
no, 10-20% of the population has 2 mutations. you are only at risk for NTD if you have inc homocystine and AND 2 mutations
70
2 mutations in MTHFR and inc homocysteine have an increased risk for what
NTD
71
how do we make homocysteine levels go back to normal?
ingest enough folate
72
why is folic acid important?
daily folic acid of 400ug reduces homocysteine levels up to 70%
73
what can reduced homocysteine levels prevent
NTD, cleft lip and palate defects, heart defects, limb reduction defects, UT defects, cancer, strokes
74
when do we need to start having folic acid in our diet in relation to pregnancy
one month before conception through the first few weeks of pregnancy, which is HARD bc 50% of pregnancies are unplanned
75
what does the US public health service recommend to women capeable of becoming pregnant
consume 400 micrograms or .4 mg of folic acid daily throughout childbearing years to reduce risk of having a pregnancy affected by NTD
76
what foods are rich in folate
liver, dark leafy greens, citrus fruits, nuts, seeds, legumes, dried peas/beans, lentils, enriched whole grains/cereals
77
if there is a family hx of NTD, how much folic acid should mothers intake
4000 micrograms or 4mg which is 10 times the normal recommended
78
locus heterogenity?
many different genes can cause the same phenotype
79
ex of locus heterogeneity?
osteogenesis imperfecta and noonan
80
multifactorial?
multiple additive factors are needed to reach disease threshold
81
monozygotic twins are great for studying what
environmental effect on disease bc their genes are identical
82
what is concordance?
when twins have a similar trait
83
discordance?
twins do not have a similar trait
84
a high concordance rate means what
when one twin has a trait, the other will likely have it too
85
what are some common concorgance traits?
height, BMI, autism, fingerprints, measles
86
monozygotic twins share ___% of genetic material while dizygotic twins share___%
100,50
87
what does a heritability of 1 suggest?
trait is highly genetic
88
how do we calculate heritability
2* (MZ concordance-DZ concordance)
89
what can account for differences in MZ twins
different uterine environments, postnatal environments, somatic mutations, methylations patterns
90
why is schizophrenia hard to study
so many different symptoms and phenotypes
91
schizophrenia is linked to receptors with what NT receptor interactions
glutamate
92
MCC of cardiovascular disease
CAD
93
leading cause of death worldwide
cardiovascular disease
94
family hx of this disease increases ones risk for getting the disease by 2
cardiovascular disease
95
what type of disease is cardiovascular disease
multifactorial
96
what is dilated cardiomyopathy
increase in ventricular size and impaired contraction
97
how is dilated cardiomyopathy inherited
mostly autosomal dominant but there are XLR and mitochondrial forms
98
what is hypertrophic cardiomyopathy
thickened heart muscle
99
how is hypertrophic cardiomyopathy inherited
autosomal dominant
100
what is long QT syndrome
delated repolarization
101
what are ppl with long QT syndrome at risk for
fatal arrhythmia
102
how is long QT syndrome inherited
AD mutations
103
how is long QT syndrome treated
potassium channel blocking meds
104
this is the leading cause of adult blindness, kidney failure, and lower limb amputation
diabetes
105
diabetes is a major risk factor for what
heart disease and stroke
106
what is maturity onset diabetes of the young (MODY)
autosomal dominant condition that is a single gene disorder
107
T or F: all cancer is genetic, but not all cancer is inherited
T
108
what variables can pt control when looking at risk for multifactorial diseases
diet, screening, lifestyle
