A 9-year old girl who had a very rare genetic immune disease called WHIM while growing up, was apparently cured in her 30s, spontaneously. Scientists have attributed it to a phenomena called Chromothripsis or ‘chromosome shattering’ during which chromosome pairs disintegrate and reassemble themselves into random and chaotic positions, with hundreds of gene alleles getting lost forever in the shuffling. Researchers claim that the woman might have got rid of the defective gene during one such scrambling of DNA in one of her blood stem cells. Their findings were published in the journal Cell.
The little girl was the first known case of a person who suffered from WHIM (Warts, Hypogammaglobulinemia, Infections, and Myelokathexis) syndrome back in 1964 and was documented in two reports in The New England Journal of Medicine. People who are afflicted with WHIM suffer from recurring infections due to poor immunity and when they grow into adulthood they may develop lung scarring, hearing loss and are also highly susceptible to human papillomavirus, which causes warts on their skin and genital areas that could turn cancerous.
She also grew up battling several infections due to the abnormally low levels of a certain white blood cell which is needed to fight microbes. In 2003, researchers linked WHIM to the presence of a defective copy of a gene called CXCR4 which encodes the chemical messenger, called chemokines. Patients having WHIM have one normal copy of CXCR4 and a defective copy that causes the receptor to be overactive—it doesn’t shut off when it’s supposed to. This somehow causes white blood cells to “get stuck” in the bone marrow instead of entering the bloodstream, says Philip Murphy, an immunologist at the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland.
When the little girl, who is now 59yrs old, walked into a clinic to get her two daughters tested for the same inherited condition, they did indeed have classic symptoms of WHIM. But the doctors were pleasantly surprised to hear that their mother was doing absolutely fine and had no warts or serious infections since her late 30s. Chromosomal analysis further showed that, one copy of chromosome 2 was 15% shorter than the other copy and the woman’s white blood cell no longer carried the faulty CXCR4 mutation, although other cell types still carried it. Whole genome sequencing confirmed that, one of the stem cells in her blood underwent a chromothriptic event and deleted the defective CXCR4 and 163 other normal genes. This event transformed the unhealthy WHIM cell to a healthy non-WHIM cell and since it was a blood stem cell, they replicated to give her a supply of normal white blood cells. Since her immune system returned to normal, her infections and warts subsided too. “So it sounds kind of crazy and farfetched,” Murphy said, “but that’s actually what happened.”
Murphy says he’d also add one other point of interest to the study, “Doctors have all heard of patients termed ‘miracle cures,’” he said, “and now I think anyone who has a patient like that should consider looking for chromothripsis as a potential natural explanation for the miracle. I think that’s one important thing that falls out of this research.”
More can be read at http://bit.ly/16wBzBk
The original paper can be accessed here.