#RoyalBlood #RoyalDisease
May 31, 2020
Images of the Victorian Royal Family
Hemophilia is a genetic disease also termed as 'The Royal disease'
Hemophilia is a genetically inherited blood-clotting disorder caused by the deficiency of
clotting factors. It is characterized by the inability to properly form blood clots. Due to
this,even a minor trauma can lead to profuse hemorrhage.
The 3 types of Hemophilia are Hemophilia A(max%), Hemophilia B and Hemophilia C
caused by the deficiency of clotting factors VIII, IX, and XI respectively.
The affected gene is present in the X-chromosome. It can be passed along generations
by hereditary transmission in an X-linked recessive pattern.
, Genotypically, males (XY) have one X and one Y chromosome. Whereas, females (XX)
have two X chromosomes.
Due to the recessive pattern of inheritance in hemophilia, when children inherit the
affected X-chromosome, the affected male offspring will always express the
disease whereas most females act as carriers of the disease. This is because the carrier
females have another copy of X-chromosome that contains a normal gene aiding the
formation of clotting factors. Whereas, males have only one copy of X-chromosome due
to which they always express the disease if they inherit the affected gene.
The treatment of Hemophilia is mainly by replacement therapy.
The probability of genetic transmission can be better understood using Punnett
squares.
Scenario 1: (Carrier mother & Unaffected father)
Unaffected father
X Y
Carrier
XX XY
mother X
X XX XY
The red X denotes the chromosome carrying the hemophilia gene
XX stands for normal female
XX stands for carrier female
XY stands for normal or unaffected male
XY stands for affected or haemophilic male
May 31, 2020
Images of the Victorian Royal Family
Hemophilia is a genetic disease also termed as 'The Royal disease'
Hemophilia is a genetically inherited blood-clotting disorder caused by the deficiency of
clotting factors. It is characterized by the inability to properly form blood clots. Due to
this,even a minor trauma can lead to profuse hemorrhage.
The 3 types of Hemophilia are Hemophilia A(max%), Hemophilia B and Hemophilia C
caused by the deficiency of clotting factors VIII, IX, and XI respectively.
The affected gene is present in the X-chromosome. It can be passed along generations
by hereditary transmission in an X-linked recessive pattern.
, Genotypically, males (XY) have one X and one Y chromosome. Whereas, females (XX)
have two X chromosomes.
Due to the recessive pattern of inheritance in hemophilia, when children inherit the
affected X-chromosome, the affected male offspring will always express the
disease whereas most females act as carriers of the disease. This is because the carrier
females have another copy of X-chromosome that contains a normal gene aiding the
formation of clotting factors. Whereas, males have only one copy of X-chromosome due
to which they always express the disease if they inherit the affected gene.
The treatment of Hemophilia is mainly by replacement therapy.
The probability of genetic transmission can be better understood using Punnett
squares.
Scenario 1: (Carrier mother & Unaffected father)
Unaffected father
X Y
Carrier
XX XY
mother X
X XX XY
The red X denotes the chromosome carrying the hemophilia gene
XX stands for normal female
XX stands for carrier female
XY stands for normal or unaffected male
XY stands for affected or haemophilic male
