1. Is it possible for a female carrier to have a daughter who has hemophilia? Explain your answer using terms such as sex-linked inheritance, sex-linked genes, dominant, recessive, and X and Y chromosomes.
Sex-linked inheritance is when a gene is located on a sex chromosome, usually a mutated gene that can cause a disorder. The sex chromosomes are X and Y. The combination of two sex chromosomes determines a person’s sex. XX is female and XY is male. Hemophilia is a rare, sex-linked inherited blood clotting disorder that causes blood to clot abnormally resulting in slower clotting. Hemophilia is a recessive disorder that is passed along the X chromosome (National, 2013). A recessive gene will not manifest itself unless paired with a like recessive gene or in an absence of a dominate gene to suppress it. A carrier is a person who has the gene for a disorder, has the ability to pass on the disorder, but does not develop the disorder because there is not a matching recessive gene to activate it and there is a dominant gene to block it.
A woman who is a carrier for hemophilia will be represented as XXh. If a male is XhY the hemophilia gene on the lone X chromosome is enough for the condition to manifest itself (National, 2013). A woman who is a carrier of hemophilia can give birth to a daughter who has hemophilia only if the male has hemophilia and transmits the recessive gene on his X chromosome. If a woman who is a carrier mates with a man who has the disorder they could have a daughter with hemophilia. The offspring of a carrier female and afflicted male would have a 25% chance of being XXh, XY, XhY, or XhXh, giving a 25% chance their daughter would have it.
2. Choose a specific trait such as eye color, and explain the meaning of homologous chromosomes.
A set of homologous chromosomes contains a pair of matching chromosomes. One of the chromosomes come from the