Guys this is sirius and important, help 

I got baby recently and his blood type is A+

Mine is B+ and wife is O+, doc say its quite impossible.

How come? Have anyone experience the same?

p/s don't think my wife commit adultery or something...    

UPDATE at 4.26pm

Guys, many thanks for your input! 

Finally can reach both my parent. Looks like there's light in the end of tunnels!

Both my parent blood group is treeennnggg... both A+ !!!

So to satisfied the mystery:

Both parent A+ = me:A+

(me:A+)  +  (wife:O+)  = son:A+

So the clinic where I go for pre-marital blood check got my blood wrong 

Will do blood test tomorrow to reconfirm this however

For the green hat theories guys, sorry to disappoint ur all