Study the following carefully - (AIIMS May 2013)
Read the pedigree. Inheritance pattern of the disease in the family is -
X Linked Recessive
o Similar to above question, only males are manifesting disease and females are acting as carrier
o It will be easier to solve this question if I will change the represention of Pedigree
XY (Normal male) XbX (Carrier female)
YX XdX XY XdY XX
(Normal male) (Carrier female) (Normal male) (Affected male) (Normale female)
XdY XdY XY XY XdX XX
o The Pedgree starts from normal male and carrier female.
o Carrier female transfer the mutated X-chromosome to half the male children and half of the female children.
o Second generation pedgree starts when one of the carrier female marries to normal male.
o Here also she transfer her mutated X-chromosome to half of the male children and to half of the female children. Also know
X-linked recessive disorders
Duchene muscular dystrophy
Hemophilia A & B
Chronic granulomatous dis.
X-linked domainant disorder
Vitamine D resistant rickets