Question

you meet a young male with hemophilia, an x - linked recessive disorder. while talking to him, he mentions that his maternal grandfather also had hemophilia, but his parents do not. which of the following statements about his family would be correct? correct answer(s) his maternal grandmother also had hemophilia. he could pass the gene for hemophilia on to his future daughters. he could pass the gene for hemophilia on to his future sons. his sister would also be a hemophiliac. his father is a genetic carrier of hemophilia. his mother is a genetic carrier for hemophilia.

Explanation:

Hemophilia is X - linked recessive. Males have XY chromosomes. The young male with hemophilia got his X chromosome from his mother. Since his maternal grandfather had hemophilia, his mother must be a carrier as she got the affected X from her father. He can pass the hemophilia - carrying X chromosome to his future daughters. His maternal grandmother's status is not determinable from the given information. He cannot pass the gene to sons as they get the Y from him. His sister's status depends on the mother's other X chromosome and the father's X, so we can't say she is a hemophiliac. Fathers of males with X - linked recessive disorders are not carriers as they don't pass on the X for this disorder.

Answer:

He could pass the gene for hemophilia on to his future daughters. His mother is a genetic carrier for hemophilia.