What is haemophilia? i have heard that girls donot have this disease. why?

Question

What is haemophilia... why does it not occur to girls/ women (some people say that).
Also tell me how are blood groups detected.. like- Positve A, B, O, AB.
what is difference between positve and negative blood group.

please answer them.
thank you.

Answer 1

Haemophilia or hemophilia is the name of several hereditary genetic illnesses that impair the body's ability to control bleeding, an impairment known technically as bleeding diathesis. Genetic deficiencies and a rare autoimmune disorder may cause lowered plasma clotting factor activity so as to compromise blood-clotting; when a blood vessel is injured, a scab does not form and the vessel continues to bleed for an excessive period of time. The bleeding can be external, if the skin is broken by a scrape, cut or abrasion, or it can be internal, into muscles, joints or hollow organs. The result may be visible (e.g., skin bruises) or subtle (e.g., melena, hematuria, or bleeding in the brain). This is called the lack of clotting factors - Haemophilia A has a lack of the clotting factors 8 - and Hemophilia B has a lack of the clotting factors 9 - Hemophilia A occurs in 90% of cases
Females possess two X-chromosomes, whereas males have one X and one Y chromosome. Since the mutations causing the disease are recessive, a woman carrying the defect on one of her X-chromosomes may not be affected by it, as the equivalent allele on her other chromosome should express itself to produce the necessary clotting factors. However the Y-chromosome in men has no gene for factors VIII or IX. If the genes responsible for production of factor VIII or factor IX present on a male's X-chromosome is deficient there is no equivalent on the Y-chromosome, so the deficient gene is not masked by the dominant allele and he will develop the illness.

Since a male receives his single X-chromosome from his mother, the son of a healthy female silently carrying the deficient gene will have a 50% chance of inheriting that gene from her and with it the disease; and if his mother is affected with haemophilia, he will have a 100% chance of being a haemophiliac. In contrast, for a female to inherit the disease, she must receive two deficient X-chromosomes, one from her mother and the other from her father (who must therefore be a haemophiliac himself). Hence haemophilia is far more common among males than females. However it is possible for female carriers to become mild haemophiliacs due to lyonisation of the X chromosomes. Haemophiliac daughters are more common than they once were, as improved treatments for the disease have allowed more haemophiliac males to survive to adulthood and become parents. Adult females may experience menorrhagia (heavy periods) due to the bleeding tendency.The pattern of inheritance is criss-cross type.This type of pattern is also seen in colour blindness.

As with all genetic disorders, it is of course also possible for a human to acquire it spontaneously (de novo), rather than inheriting it, because of a new mutation in one of their parents' gametes. Spontaneous mutations account for about ⅓ of all haemophilia A and 1/5 of all haemophilia B cases. Genetic testing and genetic counseling is recommended for families with haemophilia

Blood group AB individuals have both A and B antigens on the surface of their RBCs, and their blood serum does not contain any antibodies against either A or B antigen. Therefore, an individual with type AB blood can receive blood from any group (with AB being preferable), but can donate blood only to another group AB individual.
Blood group A individuals have the A antigen on the surface of their RBCs, and blood serum containing IgM antibodies against the B antigen. Therefore, a group A individual can receive blood only from individuals of groups A or O (with A being preferable), and can donate blood to individuals of groups A or AB.
Blood group B individuals have the B antigen on their surface of their RBCs, and blood serum containing IgM antibodies against the A antigen. Therefore, a group B individual can receive blood only from individuals of groups B or O (with B being preferable), and can donate blood to individuals of groups B or AB.
Blood group O (or blood group zero in some countries) individuals do not have either A or B antigens on the surface of their RBCs, but their blood serum contains IgM anti-A antibodies and anti-B antibodies against the A and B blood group antigens. Therefore, a group O individual can receive blood only from a group O individual, but can donate blood to individuals of any ABO blood group (ie A, B, O or AB). If a blood transfusion is needed in a dire emergency, and the time taken to process the recipient's blood would cause a detrimental delay, O Neg blood is issued.

Answer 2

Alright firstly, hemophilia is a genetic disorder in the X chromosome which leads to a reduced level of platelets production. Platelets are the material which seal of blood shut when we bleed, simply put. In this condition it may take longer or may not happen at all.

Secondly, because it happens on the X chromosome women have two X chromosomes so one contradicts the other. However men have a smaller and less effective Y chromosome which doesn't contradict the X. Some men are far more likely to get it. Women can get it but only if they have two affected X chromosomes.

Also simply put again when a person has a blood transfusion and has A blood, B blood attacks when a person has B blood, A blood attacks. And when a person has O blood no blood attacks.

Lastly the positive negative thing, this is another protein on cells which if a positive is put into a negative body the body will attack it thinking its bacteria.

Answer 3

Haemophilia is a disease in which the blood looses its property of clotting which would mean that even a small cut on skin can be fatal enough to cause death. It is a hereditary disease and is linked with 'Y' chromosome. You may be aware that 'Y' chromosome is always carried by males. So females have no chance of inheriting this disease.

About testing of blood groups you must understand that each type of blood contains two types of proteins- antibodies and antigens. Any sample of blood having a different antibody than the one that it has will coagulate the other one. It is this property of the blood, i.e. antibody-antigen reaction, that is made use of to find out blood groups.

As regards positive and negative bloods, these are due to a particular type of protein in blood called Rh factor. If a person has it, the blood is Rh positive and if not the blood is Rh negative. Rh factor was first discovered in Rhesus monkeys hence the name. Rh negative blood is rare and O negative is extremely rare.
Hope I made it clear to you.

Answer 4

Hemophilia is a rare blood disease in which it lacks the special proteins that clot blood. The clotting helps blood from bleeding. A male with hemophilia can be pushed and they would bleed internally and will continue to bleed without help. A cut would continue bleeding, and so on and so forth.

It does not occur in females because of the fact that the gene for this disease is carried on the X chromosome carried by the female. A female only serves as a carrier to this disease. Females has two copies of the X chromosome, and if one X chromosome has the gene for hemophila -- it has a "back up copy" whereas the male only has one copy of the X chromosome inherited from the mother. So, if a carrier mother passes on an X chromosome with the gene to a son, he will have hemophilia. If she passes it to her daughter, her daugher will be a carrier.

I find the question about blood types and differences too long to answer and would be quite difficult to understand with a detailed explanation. I leave it to wikipedia for that :)

http://en.wikipedia.org/wiki/Blood_type

Answer 5

Haemophilia or hemophilia is the name of several hereditary genetic illnesses that impair the body's ability to control bleeding
Hemophilia figured prominently in the history of European royalty and thus is sometimes known as "the royal disease". Queen Victoria passed the mutation to her son Leopold and, through several of her daughters, to various royals across the continent, including the royal families of Spain, Germany, and Russia. Tsarevich Alexei Nikolaevich, son of Nicholas II, was a descendant of Queen Victoria and suffered from haemophilia.
it is x-linked trait
Since a male receives his single X-chromosome from his mother, the son of a healthy female silently carrying the deficient gene will have a 50% chance of inheriting that gene from her and with it the disease; and if his mother is affected with haemophilia, he will have a 100% chance of being a haemophiliac

for the second question try;
http://en.wikipedia.org/wiki/Blood_group#Rhesus_blood_group_system

Answer 6

Haemophilia or hemophilia is the name of several hereditary genetic illnesses that impair the body's ability to control bleeding, an impairment known technically as bleeding diathesis. Genetic deficiencies and a rare autoimmune disorder may cause lowered plasma clotting factor activity so as to compromise blood-clotting; when a blood vessel is injured, a scab does not form and the vessel continues to bleed for an excessive period of time. The bleeding can be external, if the skin is broken by a scrape, cut or abrasion, or it can be internal, into muscles, joints or hollow organs. The result may be visible (e.g., skin bruises) or subtle (e.g., melena, hematuria, or bleeding in the brain). This is called the lack of clotting factors - Haemophilia A has a lack of the clotting factors 8 - and Hemophilia B has a lack of the clotting factors 9 - Hemophilia A occurs in 90% of cases.

Genetics structure
Females possess two X-chromosomes, whereas males have one X and one Y chromosome. Since the mutations causing the disease are recessive, a woman carrying the defect on one of her X-chromosomes may not be affected by it, as the equivalent allele on her other chromosome should express itself to produce the necessary clotting factors. However the Y-chromosome in men has no gene for factors VIII or IX. If the genes responsible for production of factor VIII or factor IX present on a male's X-chromosome is deficient there is no equivalent on the Y-chromosome, so the deficient gene is not masked by the dominant allele and he will develop the illness.

Since a male receives his single X-chromosome from his mother, the son of a healthy female silently carrying the deficient gene will have a 50% chance of inheriting that gene from her and with it the disease; and if his mother is affected with haemophilia, he will have a 100% chance of being a haemophiliac. In contrast, for a female to inherit the disease, she must receive two deficient X-chromosomes, one from her mother and the other from her father (who must therefore be a haemophiliac himself). Hence haemophilia is far more common among males than females. However it is possible for female carriers to become mild haemophiliacs due to lyonisation of the X chromosomes. Haemophiliac daughters are more common than they once were, as improved treatments for the disease have allowed more haemophiliac males to survive to adulthood and become parents. Adult females may experience menorrhagia (heavy periods) due to the bleeding tendency.The pattern of inheritance is criss-cross type.This type of pattern is also seen in colour blindness.

As with all genetic disorders, it is of course also possible for a human to acquire it spontaneously (de novo), rather than inheriting it, because of a new mutation in one of their parents' gametes. Spontaneous mutations account for about ⅓ of all haemophilia A and 1/5 of all haemophilia B cases. Genetic testing and genetic counseling is recommended for families with haemophilia. Prenatal testing, such as amniocentesis, is available to pregnant women who may be carriers of the condition.


[edit] Probability
Until modern direct DNA testing, however, it was impossible to determine if a female with only healthy children was a carrier or not. Generally, the more healthy sons she bore, the higher the probability that she was not a carrier. If the RH factor of the born male is different from the mother, the child will be not affected.

It is estimated that about 0.00006% (18,000 total) of the United States population suffers from haemophilia

Answer 7

Haemophilia is popularly known as the 'bleeder's disease'.In this , the blood fails clot.
The reason for Haemophilia not to affect women is because their sex chromosomes are XX type and in men it is XY.So women can only be carriers of Haemophilia and cannot be inflicted with it.

Answer 8

Hemophalia is a diseased condition where blood fails to clot in case of injury. its gene is present on Y chromosome so it is only found in males. blood group detection is very easy. take three drops of blood on a slide and mark them as A B and D. Now take the antiserum. Put a drop of Antiserum A on drop marker as A, B on Drop B and Antiserum D on Drop D. Take a look at blood drops, those drops which coagulate represent your blood group. Like if A coagulates your blood group is A, If B then Your blood group is B is Both then AB. If none then O.If D coagulates you are +ive if not then you are -ive. hope this will help.

Answer 9

Haemophillia is a genetic diseasee which stops the blood from clotting. This means that if they cut themselves they can bleed to death. It doesn't have to be a cut either people suffering from this have died due to internal bleeding from a bruise. Men mainly have it as it is carried on the X chromosome, so a carrier female and haemophilliac male would have a 1 in 4 chance of having a haempohilliac female.
I'm sorry but I can't remember the answer for the other part. I know it has something to do with Rhesus (positive and negative) Hope it helps :-)

Answer 10

Haemophilia A (also spelled Hemophilia A or Hæmophilia A) is a blood clotting disorder caused by a mutation of the factor VIII gene, leading to a deficiency in Factor VIII. It is the most common hemophilia. Inheritance is X-linked recessive; hence, males are affected while females are carriers or very rarely display a mild phenotype. 1 in 10,000 males are affected.

Hemophilia leads to a severely increased risk of bleeding from common injuries. The sites of bleeding are:

joints
muscles
digestive tract
brain
The muscle and joint hemorrhages are quite typical of hemophilia, while digestive tract and cerebral hemorrhages are also germane to other coagulation disorders.

Females possess two X-chromosomes, whereas males have one X and one Y chromosome. Since the mutations causing the disease are recessive, a woman carrying the defect on one of her X-chromosomes may not be affected by it, as the equivalent allele on her other chromosome should express itself to produce the necessary clotting factors. However the Y-chromosome in men has no gene for factors VIII or IX. If the genes responsible for production of factor VIII or factor IX present on a male's X-chromosome is deficient there is no equivalent on the Y-chromosome, so the deficient gene is not masked by the dominant allele and he will develop the illness.

Since a male receives his single X-chromosome from his mother, the son of a healthy female silently carrying the deficient gene will have a 50% chance of inheriting that gene from her and with it the disease; and if his mother is affected with haemophilia, he will have a 100% chance of being a haemophiliac. In contrast, for a female to inherit the disease, she must receive two deficient X-chromosomes, one from her mother and the other from her father (who must therefore be a haemophiliac himself). Hence haemophilia is far more common among males than females. However it is possible for female carriers to become mild haemophiliacs due to lyonisation of the X chromosomes. Haemophiliac daughters are more common than they once were, as improved treatments for the disease have allowed more haemophiliac males to survive to adulthood and become parents. Adult females may experience menorrhagia (heavy periods) due to the bleeding tendency.The pattern of inheritance is criss-cross type.This type of pattern is also seen in colour blindness.

As with all genetic disorders, it is of course also possible for a human to acquire it spontaneously (de novo), rather than inheriting it, because of a new mutation in one of their parents' gametes. Spontaneous mutations account for about ⅓ of all haemophilia A and 1/5 of all haemophilia B cases. Genetic testing and genetic counseling is recommended for families with haemophilia. Prenatal testing, such as amniocentesis, is available to pregnant women who may be carriers of the condition.