
We are searching data for your request:
Upon completion, a link will appear to access the found materials.
I see a family in which it has only one daughter. The blood group of the mother is AB positive and the father is B positive, but the blood group of the daughter is O negative.
When she was young, they apply to shift abroad permanently. When the Embassy test their blood group, the doctor said "She is not your daughter because of her blood group".
How is it possible? Why is she not the daughter of their parents?
Each person has two alleles for the blood type. The two A and B alleles are dominant. So, you don't need A/A to end up with blood type A, it could also be A/O. Having both A and B results in blood type AB. Having none of these, results in blood type O.
Following these rules, from parents being AB and B (genetically either B/B or B/O) you would expect these possible blood types for their children: - A/B - A/O - B/B - B/O
The Rh factor (positive or negative) is inherited similarly. The positive allele is dominant, so genetically +/+ or +/- would be positive, only -/- is negative.
There is a rare case of a "cis AB" mutation, where the A and B antigens are in just one allele (wiki, paper). Then the genetic alleles of an AB type could be AB (in one allele) and O. The children of the couple could then be - AB/B - AB/O - B/O - O/O
So, there would be two possibilities for the case you describe.
The parents are not the biological parents of the child.
The mother is cisAB/O +/- and the father B/O -/-
edit: or a third way would be of course some de novo mutation in the child, resulting in the loss of A/B from the mother
edit2: maybe to answer your actual question "How can a child not be the child of its parents?"… adoption, in-vitro fertilization with donated eggs and/or sperm from other people, mix-up in the hospital…
Using Blood Typesas a Cheap Paternity Test
The earliest paternity test was a comparison of blood types. This analysis cannot provide absolute proof of fatherhood. But it can often eliminate a potential father.
Plus, you may already know each person’s type from medical records. In that case the cost is zero.
TIP: If a man was ever in military service, his type will be on his dog tags.
Even if you don’t already have this information for everyone, this approach may be less expensive than a DNA paternity test.
So you may want to identify the missing blood types before you incur the expense of a DNA paternity test.
Briefly, here’s how blood typing works.
There are four common values: A, B, AB, and O.
If you know the mother and child’s type, then you can use the following chart to narrow the list of possible types for the father.
Find the child's value in yellow and the mother's value in blue. Read down the child's column and across the mother's row to find the green cell where they intersect.
The letters listed in that cell are the possible ABO groups of the father.
For example, if the child is A and the mother is O, the father MUST be A or AB. It is biologically impossible for a man with B or O blood to have fathered this child.
NOTE: The two blank cells represent impossible combinations between mother and child, regardless of the father.
Important Limitations of Blood Types
As you can see in the chart, there are some combinations of mother and child that show all four possibilities and cannot, therefore, eliminate any possible father.
The most important limitation is that knowing this information can, at best, only eliminate someone. By itself, it cannot prove that any given man is the child's father.
However, if the mother knows there are only two possible candidates, eliminating one of them will tell her that the other one is the father.
If this doesn’t resolve the question—-or if you need a positive paternity test for legal purposes—-you must still get a DNA paternity test.
While many companies can provide such a test, the one I am most confident in isꃪsyDNA.
TIP: If your paternity issue involves child support or custody issues, you need to order their LEGAL paternity test that is court admissible. If this knowledge is just for personal information, the home test kit is sufficient.
What if the Father is Unknown?
In some cases a child's biological father may be an unknown man. In that case DNA testing can solve the mystery, just like it has for thousands of adoptees. Read my page on Find Birth Parents to learn more.
HERE ARE MY RECOMMENDEDNA TESTING COMPANIES. CLICK THE LINKS TO SEE CURRENT PRICING.
Facebook Page
See my DNA Testing Adviser Facebook Page ਏor news and discussions about DNA testing, genealogy and adoption topics.
Read my groundbreaking story at FindingFamilyBook.com
Click image above to see the reviews on Amazon.com.
My easy-to-understand introduction to genetic genealogy is just $3.99 on Amazon .
Blog Subscription
Options in the box below let you receive my blog posts through an RSS Reader.
Download my free PDF file with nearly 300 links to valuable genetic genealogy resources.
This site is designed for educational purposes only.
The author, Richard Hill, is not engaged in rendering medical or legal advice.
How it is possible that blood group shows that a person is not the son or daughter of their parents? - Biology
When two people share the same H uman L eukocyte A ntigens (abbreviated as HLA ), they are said to be a "match", that is, their tissues are immunologically compatible with each other. HLA are proteins that are located on the surface of the white blood cells and other tissues in the body.
|
|
|
|