Hermansky-Pudlak Syndrome (HPS) is a genetic metabolic disorder which causes albinism, visual impairment, and a platelet dysfunction with prolonged bleeding. in some patients there is accumulation in the cells of a wax-like (hence the name) substance presently known as “ceriod”, which is associated with inflammatory bowel disease, pulmonary fibrosis, and kidney disease. Hermansky-Pudlak syndrome was originally identified in two patients in Czechoslovakia in 1959. The doctors involved were Hermansky and Pudlak. HPS has since been identified in people all over Planet Earth – of interest to epidemiologists is this rare group of diseases is very prevalent among Puerto Rican people due to a “Founders Effect” on that island. One in 20 people in the northwestern part of Puerto Rico carry the HPS1 gene. One in 1,600 in this region have HPS1. HPS3 is also common on the island, primarily in the central region. One in 60 people on the island carry the syndrome. Across our planet, the incidence of HPS is somewhere between 1 in 500,000 to 1 in a 1,000,000. Note that this is a conservative estimation because the disorder is so frequently undiagnosed. There are indications HPS may also occur with greater frequency in Japan and Switzerland.
So far, there are at least ten genes involved, each with a separate type of Hermansky-Pudlak syndrome.
- AP3B1
- AP3D1 – hot off the presses – a reader sent this in two hours after I first posted
- BLOC1S3
- BLOC1S6
- DTNBP1
- HPS1
- HPS3
- HPS4
- HPS5
- HPS6
“Mutations in the HPS1 gene cause approximately 75 percent of the Hermansky-Pudlak syndrome cases from Puerto Rico. About 45 percent of affected individuals from other populations have mutations in the HPS1 gene. Mutations in the HPS3 gene are found in about 25 percent of affected people from Puerto Rico and in approximately 20 percent of affected individuals from other areas. The other genes associated with Hermansky-Pudlak syndrome each account for a small percentage of cases of this condition.” Ominously, there are dozens of people with diagnosed with Hermansky-Pudlak syndrome where the genetic cause of the disorder is unknown. That would imply either more genes are lurking or there is some other factor, presumably epigenetic or environmental.
more to follow – check out https://www.hpsnetwork.org/
