Genetic Disorders Expert Forum
blood type
About This Forum:

Questions in the Genetics Forum are being answered by medical professionals and experts. This forum is for questions and support regarding a person’s predisposition to a variety of medical conditions such as Ashkenazi Jewish Diseases, Bleeding Disorders, Blood Clotting Disorders, Cancer Genetics and Hereditary Cancer Syndromes, Chromosome Abnormalities, Congenital Birth Defects, Cystic Fibrosis, Family History, Fragile X Syndrome, Infertility, Newborn Screening, Rare Genetic Disorders, Prenatal Screening and Testing.

Font Size:
A
A
A
Background:
Blank
Blank
Blank
This expert forum is not accepting new questions. Please post your question in one of our medical support communities.
Blank Blank

blood type

my husband blood type O and me blood type O positive why is my son he's blood type B positive is it possible?
Related Discussions
264002_tn?1193282555
I hope that the following background information helps to answer your question.  Blood type is an example of a trait determined by a single gene. Each of us has two copies of the gene for blood type.  We inherit one copy of the gene from our mother, and the other copy from our father.  There are three different forms (called alleles) of the gene for blood type called A, B, and O.  Blood type is determined by the combination of alleles inherited from our parents.  

A person’s blood type is called their phenotype, and the different genetic combination of the forms of the gene is called a genotype.   An example of a genotype would be OB.  In this example, the person has two forms of the gene, O and B.  This person’s blood type or phenotype would be type B blood.  As the previous poster mentioned, O is a recessive form of the gene.  In order for an individual to have type O blood, they would have inherited one “O” allele from the mother and one from the father and have the genotype OO.   A and B forms of the gene are codominant and can both be expressed together.    
2 Comments
Blank
97628_tn?1204465633
Type O blood is recessive so,  to my limited understanding, two type O parents each have O-O genotype and will almost always have a type O child, barring a mutation of course.
So, assuming no initial error in blood typing was made with any of the parties, with a mutation it  is possible, but the mutation is not likely.

There are genetic tests available for maternity/paternity that are more in depth than blood typing.
Blank
Avatar_n_tn
A related discussion, Blood and Semen was started.
Blank
Continue discussion Blank
MedHelp Health Answers
Blank
Weight Tracker
Weight Tracker
Start Tracking Now
RSS Expert Activity
233488_tn?1310696703
Blank
New Cannabis Article from NORTH Mag...
Jul 20 by John C Hagan III, MD, FACS, FAAOBlank
242532_tn?1269553979
Blank
3 Reasons Why You are Still Binge E...
Jul 14 by Roger Gould, M.D.Blank
242532_tn?1269553979
Blank
Emotional Eating: What Your Closet ...
Jul 09 by Roger Gould, M.D.Blank