1. STANDARD Assume rare receswsive X-linked mutation. What is the risk for a child born to women "j" (marked also with "?", figure below)?
   
   
2. STANDARD Assume a dominant mutation with penetrances P(A|DD)=P(A|DN)=1, and P(A|NN)=0, and frequency of D allele of 0.05.
   1. What is the risk for the next child born in family C (figure below)? What is the relative risk, compared to population prevalence?
   2. What is the risk for the next child born in family D? What is the relative risk, compared to population prevalence?
   
   
   
3. MEDIUM Assume a mutation with penetrances P(A|DD)=P(A|DN)=1, and P(A|NN)=0.001, and frequency of D allele of 0.001. For the disease gene, there is test which can detect 80% of mutations present in population. In pedigree D, affected parent tested negative (no mutation detected).
   1. What is the risk for the next child born in family D?
   2. What is the relative risk, compared to population prevalence?
4. Assume a susceptibility mutation with penetrances P(A|DD)=0.5, P(A|DN)=0.3, and P(A|NN)=0.05. Frequency of D allele is 0.01.
   1. STANDARD What is population prevalence of disease?
   2. STANDARD What is the distribution of genotypes in diseased people?
   3. MEDIAN What is the relative risk for a (first) child born in a family where ONE parent is ill, compared to population prevalence? You may want to use some approximation in order to move quickly.
   4. MEDIAN What is the relative risk for a (first) child born in a family where BOTH parents are ill, compared to population prevalence? You may want to use some approximation in order to move quickly.
5. Assume a recessive disease with mutation frequency 1/50. The mutation is the only source of the disease in the population.
   1. STANDARD What is disease frequency in the outbred population?
   2. STANDARD How much the risk of disease is increased (RR) in a progeny of first-cousin marriage, compared to population prevalence?
   3. MEDIAN How much the risk of disease is increased (RR) in a progeny of uncle-niece marriage?
   4. MEDIAN Third-cousin marriage?
6. Assume a disease mutation with frequency 1/50. Penetrances are P(A|DD)=1, P(A|ND)=0.1, P(A|NN)=0.05.
   1. STANDARD What is disease frequency in the outbred population?
   2. STANDARD How much the risk of disease is increased (RR) in a progeny of first-cousin marriage, compared to population prevalence?