Term
| Common congenital anomalies |
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Definition
i. Cardiac defects, cleft lip/palate, neural tube defects, hydrocephaly, pyloric stenosis
ii. Neural Tube Defect
1. 1-2/1000 live births
2. High morbidity
3. 90% occur with negative family history: suggests more environmental
4. MSAFP screening in all pregnancies
5. FOLIC ACID can prevent most of these neural tube defects
a. Women are supposed to have daily folic acid supplement .4mg before conception and throughout 1st trimester
b. For women who have already had a child with NTD 4mg
c. Recommended for all fertile women
6. Amenocephaly = brain and skull don’t form are lethal
7. Neural tube closes around 28 days
8. Higher the lesion the more clinical abnormalities
9. Meningocele= just spinal fluid
10. Myelomeningocele= includes spinal cord
iii. Pyloric Stenosis
1. Sons of female patients are at the highest risk |
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Term
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Definition
TWIN STUDIES- MZ VS. DZ
-high concordance MZ = strong genetic effect
-lower concordance MZ = strong environmental effect
-high concordance DZ compared with sibs = strong environmental effect
ADOPTION STUDIES
-high rate of the disorder in adopted offspring of affected parent indicates strong genetic effect |
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Term
| Common Diseases of Adult Life |
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Definition
i. Diabetes, hypertension, coronary artery disease, stroke, breast cancner, colon cancer, obesity, epilepsy, autoimmune disorders, multiple sclerosis, schizophrenia, affective disorders, alcoholism, Alzheimers, autism
ii. Mixture of genetics and then environment (health, lifestyle)
iii. Coronary Artery Disease
1. Leading cause of death in the US
2. Genetic factors
a. AD familial hyperlipoproteinemia- defect in LDL receptor
b. Other genes involved in lipid metabolism and transport
3. Environmental factors
a. Smoking, obesity, consumption of saturated fats, sedentary lifestyle
iv. Diabetes
1. Type 1: insulin dependent
a. Risk to first degree relative 6% vs. .4% general population
b. Highest risk is the offspring of affected fathers
c. 30-50% concordance in MZ twins means genetic and environmental
d. Autoimmune factor- body attacks islets of langerhaans
e. Viral infection plays a role: Cox Sacchie virus
2. Type 2: insulin independents
a. 90% concordance in MZ twins means very genetic
b. obesity plays a role and insulin resistance
c. risk to first degree relatives 10-15%
d. Treatment: diet and exercise
3. MODY: maturity onset diabetes of the young
a. Type 2 DM with onset prior to 25 yrs
b. AD inheritance 6 different genes that can cause MODY
v. Breast Cancer
1. Most common cancer in females, 2nd to lung cancer
2. Strong familial aggregation
3. AD genes BRCA1 and 2 account for only 5-10% of US cases
vi. Alcoholism
1. 60% concordance in MZ twins, 30% in DZ twins more genetic
2. Four fold increase in risk in adopted offspring of affected parent
vii. Schizophrenia
1. Risk to offspring of affected parent is 8-10% whether raised by biological or adoptive parent. 10x the population risk
2. Shows that it is highly genetic
3. Risk to offspring of 2 affected parents 40-50%
4. 47% concordance in MZ twins, 12% DZ twins
viii. Hypertension
1. Family studies support genetic effect
2. Envrionmental factors: Na intake, reduced physical activity, psychosocial stress, obesity
ix. Obesity
1. Adoption and twin studies show genetic component
2. Environmental factors: diet and exercise
x. Alzheimer
1. Risk to first degree relative 20%
2. Late onset familial - apolipoprotein
BIPOLAR - Manic-depressive disorder
Risk to first degree relative - 5-10%
Population risk- 0.5%
75% concordance for MZ twins, 24% for DZ
UNIPOLAR - Major depression
genetic factors are also important |
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Term
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Definition
i. Chromosomal abnormalities in first trimester because of the fact that meiosis is not very efficient/perfect
ii. Single genes peak at birth since that is when you detect them, and another rise at adult for diseases that have later onset
iii. Congenital defects peak at birth and then multifactorial continue to rise in the adult since more environmental factors that interact with set of genes
d. Multifactorial disorders account for 25-50% admissions into the pediatric hospital 25-35% child mortality and even greater morbidity and mortality in adult
e. In these disorders there is a slight liability in general population but in siblings of affected people the liability goes up, there is a shift.
f. Multifactorial conditions: risk to family members is greater than general population risk but lower than risk for a Mendelian trait.
i. Risk in family is more since it is genetics but lower than mendelian because not always passed on you need the environmental factor.
g. Multifactorial Traits recurrence Risk: What traits about the defect make it more of a risk?
i. Severity: more severe= more risk
ii. Sex of proband: if it is usually a male mutifactorial defect, then if a girl gets it the female probably has a lot more severe of a case
iii. Degree of relationship: closer relationship the higher the risk
1. First Degree relatives 4%
a. See here that even if a family has a defect in a child, the chances of them having another child with that defect is still pretty low
2. Second Degree relatives .6%
3. Third degree relatives .3%
4. General Population .04%
iv. Number of family members affected: more people affected the higher the risk
v. Age of onset- earlier on = more risk
vi. Consanguinity |
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Term
| Common Multifactorial Disorders |
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Definition
1)Common diseases of adult life - diabetes, hypertension, coronary artery disease
2)Common congenital anomalies - cardiac defects, cleft lip/palate, neural tube defects |
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