As we discussed in âlectureâ, Rh is the most complex of theblood group types, involving at least 45 different antigens. Themost clinically important antigen, D orRhO, is encoded by the gene RhD whichis found on chromosome 1. Individuals that are Rh-positive haveeither one or two RhD genes, whereas the Rh-negativephenotype is caused by the absence of the RhD gene. (Theantithetical allele d does not exist, however the letter"d" is used to indicate the D-negative phenotype). For the purposeof this homework, we will simplify things. Assume that the Rh bloodgroup has only two alleles: the Rh-positive allele (D) andthe Rh-negative allele (d).
Erythroblastosis fetalis (EF) is a condition that causes themother's red blood cells to attack those of the baby as if theywere any foreign invaders. It is referred to as hemolytic anemia ofthe newborn. It is caused by anti-Rh antibodies from the motherwhich pass through the placenta and attack fetal blood cells thathappen to be Rh-positive. Babies that are at risk for thiscondition are those with Rh-positive blood, whose mothers areRh-negative (dd).
Side note: Hereâs a current headline thataddresses this condition. Itâs well worth a read!
http://www.cnn.com/2015/06/09/health/james-harrison-golden-arm-blood-rhesus/index.html
Consider a population under Hardy-Weinberg equilibrium, where thefrequency of the Rh-negative allele, d, is 0.3. What isthe frequency of crosses that could potentially produce childrenwith erythroblastosis fetalis?
As we discussed in âlectureâ, Rh is the most complex of theblood group types, involving at least 45 different antigens. Themost clinically important antigen, D orRhO, is encoded by the gene RhD whichis found on chromosome 1. Individuals that are Rh-positive haveeither one or two RhD genes, whereas the Rh-negativephenotype is caused by the absence of the RhD gene. (Theantithetical allele d does not exist, however the letter"d" is used to indicate the D-negative phenotype). For the purposeof this homework, we will simplify things. Assume that the Rh bloodgroup has only two alleles: the Rh-positive allele (D) andthe Rh-negative allele (d).
Erythroblastosis fetalis (EF) is a condition that causes themother's red blood cells to attack those of the baby as if theywere any foreign invaders. It is referred to as hemolytic anemia ofthe newborn. It is caused by anti-Rh antibodies from the motherwhich pass through the placenta and attack fetal blood cells thathappen to be Rh-positive. Babies that are at risk for thiscondition are those with Rh-positive blood, whose mothers areRh-negative (dd).
Side note: Hereâs a current headline thataddresses this condition. Itâs well worth a read!
http://www.cnn.com/2015/06/09/health/james-harrison-golden-arm-blood-rhesus/index.html
Consider a population under Hardy-Weinberg equilibrium, where thefrequency of the Rh-negative allele, d, is 0.3. What isthe frequency of crosses that could potentially produce childrenwith erythroblastosis fetalis?
