The probable genotype of the IV-3 with the perspective of autosomal inheritance will be A because he does not have condition A. Therefore both parents must be in condition A. The probable genotype of IV-3 with the perspective of set=linked inheritance will be BbY this is because he has B condition. Therefore the mothers' genotype must be XBXb and the father's genotype must be XBY. The probability of IV-4 having condition A is 1/36
Fetal alcohol syndrome is a syndrome that is a group of different symptoms or conditions that appear in a person whose mother consumed alcohol during pregnancy.
The different problems that a person may suffer from including small head size, short height, thin upper lip, smooth philtrum, etc.
Besides this, the mental health of the person is also affected and thus, the person may have memory impairment, social anxiety, etc.
Since it has been mentioned that Terrance's mother consumed alcohol throughout pregnancy and the symptoms that Terrance shows also are similar to that of a person suffering from Fetal alcohol syndrome, it can be concluded that he is suffering from this condition.
