Rhesus factor

[vevers9]

My youngest son has recently had blood tests, one of which was for his Blood Group. Both my husband and my self are Rhesus positive, as are both of my other two sons, how can my youngest son have the Rhesus negative factor?

[kags]

The Rhesus positive gene is dominant over the negative gene, therefore both you and your husband must be Rhesus positive, but each carry the negative gene. Your children will each have a 1 in 4 chance of inheriting the negative gene from both of you and therefore being negative themselves. This is what has happened with your youngest son. Good article here

http://www.mydna.com/genes/genetics/askdrdna/ask_371.html

[vevers9]

Kags, thanks very much, I am a Registered Nurse and have asked a few of the Doctors at work and they have been unable to give me an answer. Thanks again