|Cross||Genotypic ratio||Phenotypic ratio|
|AA x aa||all Aa||all A-|
|Aa x AA||1 AA : 1 Aa||all A-|
|Aa x aa||1 Aa : 1 aa||1 A- : 1 aa|
|Aa x Aa||1 AA : 2 Aa : 1 Aa||3 A- : 1 aa|
What is the phenotype of AA?
A homozygous dominant (AA) individual has a normal phenotype and no risk of abnormal offspring. A homozygous recessive individual has an abnormal phenotype and is guaranteed to pass the abnormal gene onto offspring.
What phenotypic ratio is produced between a cross of AA & AA?
according to the dominance relationships of the alleles involved. an expected phenotypic ratio of 3:1 among “A” and “a” phenotypes. Co-dominant molecular alleles typically produce a 1:2:1 ratio of “A”, “Aa”, & “a” phenotypes.
What is the allele AA?
A dominant allele is denoted by a capital letter (A versus a). Since each parent provides one allele, the possible combinations are: AA, Aa, and aa. Offspring whose genotype is either AA or Aa will have the dominant trait expressed phenotypically, while aa individuals express the recessive trait.
Is AA compatible with AS?
Compatible genotypes for marriage are:
AA marries an AS. You’ll end up with kids with AA and AS which is good. But sometimes if you’re not lucky all the kids will be AS which limits their choice of partner. AS and AS should not marry, there is every chance of having a child with SS.
Can As marry AA?
It is safe for someone with AS to marry someone with AA genotype. Two sickle cells should not even have a relationship or get married. Individuals with the AA genotype should help you prevent genetic abnormalities by marrying the AS, AC, and SS. Compatible genotypes for marriage are: AA marries an AS.
Is AA heterozygous or homozygous?
Two dominant alleles (AA) or two recessive alleles (aa) are homozygous. One dominant allele and one recessive allele (Aa) is heterozygous.
What is the predicted phenotypic ratio for the offspring?
This 9:3:3:1 phenotypic ratio is the classic Mendelian ratio for a dihybrid cross in which the alleles of two different genes assort independently into gametes.
Can as genotype change to AA?
It cannot be changed in the living time. And change depends on chance in the next generation. Genotype change is not a choice but chance. The genotypes mentioned in the question are pertaining to the genotypes of Sickle cell anemia (AA, As, ss).