Question

2. Analysis of a breeding history in pureb eding history in purebred dogs revealed a familial disease impacting some animals. Pedigree below shows the inheritance pattern in the breeding population. a) For each mode of inheritance listed below, indicate whether it is: 1: likely, 2: possible, or 3: impossible. You may make the following simplifying assumptions: 1) disease alleles are rare among animals in the general population; 2) only mothers contribute mitochondria; 1) Autosomal, sex influenced, dominant in males/recessive in females: 2) Autosomal, sex influenced, recessive in males / dominant in females: 3) X-linked Dominant: 4) X-linked Recessive: 5) Autosomal dominant, with incomplete penetrance (probability to express 0094 A Autosomal recessive, with incomplete penetrance (probability to express 2002 7) Mitochondrial:

Answer 1

Answer 1. Autosomal, sex in fluenced, dominant in males / recessive in females. Impossible Explanation As we can see the disease is dominant en fernales affecting 6 individuals while number of affected male is only 2, So this type of inheritance is impossible 2. Autosomal, Sex influenced, dominant in females i recessive in males - Possible Explanation •Sex influenced traits are controlled by genes present on autosomes and these traits are dominant in one Sex but recessive in other. Bence Number of affected female is 6 while number of affected male is 2 only. Hence this inheritence is possibly ed, dominant in females/ recessive in males. 3. X-linked dominant autosomal Sex is - Impossible Explanation This type of inheritenee's impossible as in X-linked dominant type of inheritance, the affected father passes, the disease to all of the daughters, which is not seen in this pedigree.

Explanation 4. X-linked recessive - Imposseble This gherikeneis impossible as in x-lenked recessire disease, males are more often affected than fernales and females mostly are Carriers. impossible as 5. Autosomal dominant, with incomplete penetrance (probability to express 20:) . - likely Explanation This could be possible as in this type of inheritance some individuals fails to express the trait, even though they carry the allele for the disease G. Autosomal recessive, with incomplete penetrance cprobability to express gol.) - likely Explanation This type of inheritence is likely to be happened as as is Autosomal recessive inheritence, trait affects males and females equally. to Metochondrial - & Impossible Explanation, Metochondrial genes are only inherited from the mother to all of war her offsprings, which we can clearly See is not a case here. Scanned with CamScanner