In humans, brown eye colour (B) is dominant to blue eye colour (b). In addiction, one form of colour blindness is sex linked recessive. A colour blind brown eyed man, whose mother was blue eyed, marries a blue eyed woman who has normal colour vision but whose father was colour blind. Determine the possible genetypes and phenotypes of their children.
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Little c will be the color blindness gene.
B will be the dominant brown color
Little b will be recessive (blue) eye color
Parents: XcYBb * XXcbb
Gametes: XcB - Xcb - YB - Yb * Xb - Xcb
Genotypes: XcXBb - XcXcBb - XcXbb - XcXcbb - XYBb - XcYBb - XYbb - XcYbb
Phenotype:
Normal vision/Brown eyed girl - Color blind/Brown eyed girl - Normal vision/blue eyed girl - Color blind/blue eyed girl - Normal vision/Brown eyed boy - Color blind/Brown eyed boy - Normal vision/Blue eyed boy - Color blind/Blue eyed boy
B will be the dominant brown color
Little b will be recessive (blue) eye color
Parents: XcYBb * XXcbb
Gametes: XcB - Xcb - YB - Yb * Xb - Xcb
Genotypes: XcXBb - XcXcBb - XcXbb - XcXcbb - XYBb - XcYBb - XYbb - XcYbb
Phenotype:
Normal vision/Brown eyed girl - Color blind/Brown eyed girl - Normal vision/blue eyed girl - Color blind/blue eyed girl - Normal vision/Brown eyed boy - Color blind/Brown eyed boy - Normal vision/Blue eyed boy - Color blind/Blue eyed boy