By Our Staff Reporter
KARACHI- Shortage of rare blood known as Bombay Blood Group is creating grave inconvenience for people who are suffering blood disorder in Sindh province and health experts demanded of the federal and provincial government to include blood group in Nikah Nama.
Bombay blood group also called the HH group. The peculiarity is that they do not express the H antigen. As a result they cannot form A antigens or B antigens on their red blood cells. Thus they can donate blood to anybody with ABO grouping but can receive blood only from Bombay blood group people.
This Ramadan a patient needed this unique blood type and that is when the name Bombay blood group suddenly made news in the local media special social media. Dr Awab Alvi an avid blogger led the campaign to find this rare blood type for the ailing patient.
According to Wikipedia the h/h blood group, also known as Oh or the Bombay blood group, is a rare blood type. This blood phenotype was first discovered in Bombay, now known as Mumbai, in India, by Dr. Y. M. Bhende in 1952.
The first person found to have the Bombay phenotype had an interesting blood type that reacted to other blood types in a way never seen before. The serum contained antibodies that reacted with all red blood cells’ normal ABO phenotypes. The red blood cells appeared to lack all of the ABO blood group antigens and to have an additional antigen that was previously unknown.
Individuals with the rare Bombay phenotype (hh) do not express H antigen (also called substance H), the antigen which is present in blood group O. As a result, they cannot make A antigen (also called substance A) or B antigen (substance B) on their red blood cells, whatever alleles they may have of the A and B blood-group genes, because A antigen and B antigen are made from H antigen. For this reason people who have Bombay phenotype can donate red blood cells to any member of the ABO blood group system (unless some other blood factor gene, such as Rhesus, is incompatible), but they cannot receive blood from any member of the ABO blood group system (which always contains one or more of A and B and H antigens), but only from other people who have Bombay phenotype.
Receiving blood which contains an antigen which has never been in the patient’s own blood causes an immune reaction due to the immune system of a hypothetical receiver producing immunoglobulins not only against antigen A and B, but also against H antigen. The most common immunoglobulins synthesized are IgM and IgG (and this seems to have a very important role in the low frequency of hemolytic disease of the newborn among non-Bombay offspring of Bombay mothers).
It is very important, in order to avoid any complications during a blood transfusion, to detect Bombay phenotype individuals, because the usual tests for ABO blood group system would show them as group O. Since Anti-H immunoglobulins can activate the complement cascade, it will lead to the lysis of red blood cells while they are still in the circulation, provoking an acute hemolytic transfusion reaction. This, of course, cannot be prevented unless the lab technologist that is involved has the means and the thought to test for Bombay group.
This very rare phenotype is generally present in about 0.0004% (about 4 per million) of the human population, though in some places such as Mumbai (formerly Bombay) locals can have occurrences in as much as 0.01% (1 in 10,000) of inhabitants. Given that this condition is very rare, any person with this blood group who needs an urgent blood transfusion will probably be unable to get it, as no blood bank would have any in stock. Those anticipating the need for blood transfusion may bank blood for their own use, but of course this option is not available in cases of accidental injury.
Bombay phenotype occurs in individuals who have inherited two recessive alleles of the H gene (ie: their genotype is hh). These individuals do not produce the H carbohydrate that is the precursor to the A and B antigens, meaning that individuals may possess alleles for either or both of the A and B alleles without being able to express them. Because both parents must carry this recessive allele to transmit this blood type to their children, the condition mainly occurs in small closed-off communities where there is a good chance of both parents of a child either being of Bombay type, or being heterozygous for the h allele and so carrying the Bombay characteristic as recessive. Other examples may include noble families, which are inbred due to custom rather than local genetic variety.
According to reports, Bombay Blood Group occur in 1 out of every 250,000 people some parts of world except in parts of India where the incidence has been observed to be as much as 1 in every 7,600.
Dr Saqib Ansari, Renowned Hematologist, said this is an extremely rare blood group, called Bombay Blood Group so because it was first discovered among some people in Bombay (now Mumbai) in India. He said only seven to eight Bombay blood group cases have been detected by hematologists across Pakistan so far.
He said unfortunately 90 percent population of the country does not know their blood group as there is no concept volunteer donation of blood in the society. He said government should make mandatory to mention blood types on national identity cards so that donors can be identified on the time of need.
Referring to an under treatment female Aneesa, Dr Ansari said her problems are compounded not only by the fact that she is suffering from Thalassaemia but also have rare blood group, known as the Bombay blood type. He said there are only few donors in the country who share this blood group and patients like Aneesa survive on blood transfusions, but it becomes a huge problem when one has a rare blood group because one can’t find matching donors.
He explained that blood groups are common in the country and also available for patients. He said 35 % people have O+ blood group in Pakistan, 30 % have B+ group and 15 to 20 % have A+ group. He said 5 to 10 % have A-B blood group, while only 2 to 5 % have A,B,O negative blood group.
Dr Sarfraz of Hussaini Blood Bank said 17 to 18 people identified across the Pakistan with rarest Bombay blood group so far out of which four belong to Parsi community. He said there is an acute shortage of Bombay blood group donors as majority of people do not know about their blood group.
It is time that government put in a requirement for people to get their blood group tested. It is also important as this would help the hematologists get the data and can plan things accordingly.