A couple, George and Grace had a son who was suffering from hemophilia even though none of them showed signs of hemophilia (i) State the genotype of George and Grace (ii) Using a genotypic cross work out the genotype of the couple"s son

(i) Hemophilia is a sex-linked recessive disorder, which means it's carried on the X chromosome. Women have two X chromosomes (XX) and men have one X and one Y chromosome (XY).

Since George and Grace do not show signs of hemophilia, but their son does, it means that Grace is a carrier of the disease and George is normal.

So, the genotype of George would be XY (normal) and Grace would be XHX (where H represents the hemophilia gene and X represents the normal gene).

(ii) To work out the genotype of the couple's son, we can use a Punnett square.

The Punnett square would look like this:

   X     Y
X  XX   XY
H  XH   YH

The son's genotype

(i) Hemophilia is a sex-linked recessive disorder. This means that it is carried on the X chromosome. Males have one X and one Y chromosome (XY) and females have two X chromosomes (XX).

Since George does not show signs of hemophilia, his genotype would be XY (normal). Grace, even though she does not show signs of hemophilia, must be a carrier because their son has the disorder. This means one of her X chromosomes carries the hemophilia gene and the other does not. So, her genotype would be X^HX^h (where X^H is normal X chromosome and X^h is X chromosome with hemophilia).

(ii) To work out the genotype of the couple's son, we can use a Punnett square.

The Punnett square would

(i) Hemophilia is a sex-linked recessive disorder. This means that it is carried on the X chromosome. Males have one X and one Y chromosome (XY) and females have two X chromosomes (XX).

Since George and Grace do not show signs of hemophilia, but their son does, it means that Grace must be a carrier of the disease and George must be normal. This is because the disease is recessive and carried on the X chromosome.

So, George's genotype would be XY (normal) and Grace's genotype would be XHX (where H represents the hemophilia gene and X represents the normal gene).

(ii) To work out the genotype of the couple's son, we can use a Punnett square.

The Punnett square would look like this:

   X     Y
X  XX   XY
H  XH   YH

From this, we can see that the son's genotype would be XHY, which means he has hemophilia. This is because he received the X chromosome carrying the hemophilia gene from his mother and the Y chromosome from his father.