[khanar]

I am puzzled by a question that I've seen in USMLE Consult which is saying that paroxysmal nocturnal hemoglobinuria is an X linked disorder?

How is that possible

Any elaboration would be great

thanks

 

[Sabio]

Paroxysmal Nocturnal Hemoglobinuria is an acquired disease that is the result of a somatic mutation of the phosphotidylinositol glycan protein present on the surface of blood cells.

The gene (and the related disease causing mutation) for this protein is present on the X chromosome !

But in no way should the disease be regarded as an X linked, because it's not at all a genetic disease!

Affected people will not transmit the disease to their offspring because it's a somatic mutation not a germ line mutation.

You either misunderstood the question or the question is a bad non scientific trick.