It seems like some people of blood type A and B only secrete A or B substance and not H according to some articles I have found recently. From what I have understood, it seems like the amount of H that is secreted in individuals also is different and that the amount of H that is secreted is genetically determined.

Homozygous blood type A (A/A) and B (B/B) individuals might not secrete any H at all while heterozygous blood type A (A/O) and B (B/O) individuals secretes H antigen.

The H substance is secreted in higher titre in group O individuals, the A2 group secrete less H than the O but more than the A1, group B secrete little H and AB the least.


"Differences between families in the amount of salivary H substances"
http://deepblue.lib.umich.edu/bitstream/2027.42/66443/1/j.1469-1809.1962.tb01308.x.pdf

"ABH ANTIGENS IN NORTH INDIANS' Suraksha Agarwal ABSTRACT"
http://web2.sbg.org.br/gmb/edicoesanteriores/v11n1/pdf/a15v11n1.pdf

"Rev. Brasil. Genet. V, 4, 793-805 (1982) (Brazil. J. Genetics)"
http://web2.sbg.org.br/gmb/edicoesanteriores/v05n4/pdf/a12v05n4.pdf

So H is what type O secretors secrete? And type O non-secretors don't secrete H or anything else?

Quoted from ruthiegirl

So H is what type O secretors secrete?

Yes

Quoted Text

And type O non-secretors don't secrete H or anything else?

Non secretor secrete only a minimal amount of blood type antigens A B or H into saliva and other body fluids (excluding blood).

So, non-secretors are actually "minimal secretors" rather than complete "non-secretors"?

Quoted from http://www.dadamo.com/program_advanced_secretor.htm

A Non-secretor on the other hand puts little to none of their blood type into these same fluids.

ABH secretors with low H-antigen titre in the saliva can be incorrectly classified as non-secretors from what I've understood.

Non-secreters secret low amounts, but it is also alcohol soluble instead of water soluble; I believe I read from Dr. D.

Quoted from Vista

ABH secretors with low H-antigen titre in the saliva can be incorrectly classified as non-secretors from what I've understood.

Then would a blood test (Lewis phenotyping) as opposed to a saliva test be a better determinant of secretor status?

Quoted from Patty H

Then would a blood test (Lewis phenotyping) as opposed to a saliva test be a better determinant of secretor status?

I hope so.     I did the saliva test first, and then asked my Dr. for the Lewis test at my last visit when he was taking blood for cholesterol count, etc., and I came out non-secretor on both tests.  I didn't trust my saliva test, only because I couldn't get it out of my mind that I'd done it incorrectly.  The blood test confirmed me as a nonnie, though.  But I don't know if it is more precise than saliva testing.  

Quoted from O in Virginia

I hope so.     I did the saliva test first, and then asked my Dr. for the Lewis test at my last visit when he was taking blood for cholesterol count, etc., and I came out non-secretor on both tests.  I didn't trust my saliva test, only because I couldn't get it out of my mind that I'd done it incorrectly.  The blood test confirmed me as a nonnie, though.  But I don't know if it is more precise than saliva testing.  

Same for me O in V, I did both and both confirmed my non-secretor status.

The preferred method to test for ABH secretor  status  is by PCR. Only done by reference blood banks. Mostly done to confirm unusual or very rare ABO blood group genes in a population.

Quoted from Captain_Janeway

The preferred method to test for ABH secretor  status  is by PCR. Only done by reference blood banks. Mostly done to confirm unusual or very rare ABO blood group genes in a population.

What is PCR?  Is this different from Lewis Phenotyping?  I have a rare blood antigen and my blood needed to be sent to the American Red Cross reference lab as they were they only ones who had the antibody to test it.

Quoted from Patty H

What is PCR?  Is this different from Lewis Phenotyping?  I have a rare blood antigen and my blood needed to be sent to the American Red Cross reference lab as they were they only ones who had the antibody to test it.

Polymerase Chain Reaction. PCR is a type of genetic test that relies on the duplication of certain segments of DNA that make up a specific sequence of nucleotides contained in a gene.

Lewis phenotyping and the MN and in your case the Mg antigens are screened serologically. Which means they are tested via the use of an antiserum. Sometimes the issue with using antiserums is that they are not specific enough. Certain other antigens can react with those antiserums at times giving unreliable results.

Organ transplant recipients are tested both ways via serology and PCR.

Quoted from Captain_Janeway

Polymerase Chain Reaction. PCR is a type of genetic test that relies on the duplication of certain segments of DNA that make up a specific sequence of nucleotides contained in a gene.

Lewis phenotyping and the MN and in your case the Mg antigens are screened serologically. Which means they are tested via the use of an antiserum. Sometimes the issue with using antiserums is that they are not specific enough. Certain other antigens can react with those antiserums at times giving unreliable results.

Organ transplant recipients are tested both ways via serology and PCR.

I think I understand - when you have to be ABSOLUTELY SURE, you need to use the PCR, otherwise the person could reject the organ?

How would organ transplantation be affected by someone with a rare blood antigen, like the members of my family and me?  Would that organ need to come from someone with the Mg antigen?