Allergies

I clearly belong, on my father’s side, to a family of allergic people. Happily for me, I haven’t suffered much from it (I’m allergic to drugs such as penicillin and little else, as far as I’m aware, notwithstanding the occasional itchy skin for reasons unknown). But the men in my family tell a whole different story. I remember, as a child, seeing my father’s hands full of eczema plaques (atopic dermatitis) between his fingers, which he was often scratching. This was due, he explained to us, to the fact that the reagents he used in his lab (he was a biologist), triggered allergic reactions. My brother and his sons have had more serious cases of it all through their lives. The most famous victim of this ailment appears to have been the French painter Paul Gauguin.
This morning, I received confirmation that this disposition for eczema is in fact in our genes. The Spittoon, 23andme’s blog, refers to an article published earlier this month in Nature Genetics which suggests that, although having a clear environmental component, eczema is also genetic. The study concludes that 13 percent of Europeans have a letter T at position 75978964 of their DNA sequence of both their 11th chromosomes (each inherited from one of their parents) – and that this multiplies by 1.46 their odds of getting eczema compared to the general population. I looked up my DNA bases at that precise location and found out I’m… TT. Bingo!
This may not be a very big risk – and maybe that’s why I didn’t get it myself. But another article mentioned in that same Spittoon post mentions that the very same configuration, at the same position in the same chromosome, also raises the risk for contracting Crohn’s disease, an chronic auto-immune inflammation of the bowel. For which I discovered, when I had my genes tested, that my risks are three times higher than average. It seems as though the pieces of the puzzle are starting to click into place.