Introduction[]
Sjögren's Syndrome (SS) is an autoimmune disease that targets a patient's exocrine glands, specifically the salivary glands and lacrimal glands. Discovered in 1933 by Henrik Sjögren, much is still not known about this disease.This syndrome can be found in combination with other diseases such as lupus and rheumatoid arthritis. Because of this, this can lead to a systemic infection if not spotted early. According to many scientists, SS mostly targets women who are in their forties or older. This is the most common and prevalent disease and affects almost 4 million Americans.
Phenotype[]
Figure 1. The Sjogren's syndrome Foundation's logo
The traits most accompanied by this syndrome are dry eyes and dry mouth because the exocrine glands are attacked. This reduces the amount of saliva and tears that a person produces. Since this can be accompanied by other diseases, the whole body is affected. Concentration and memory loss can be a problem as well as vaginal dryness that can lead to painful sexual intercourse.
Genotype[]
Note: Much is still not known about this disease and most of the evidence it is based on is from rheumatoid arthritis and lupus-more commonly known and researched diseases. This is a spectrum disorder and has many different SNP sites.
1. CT
At the marker rs10488631 at the 3' end of IRF5, the patient's genotype is CT. The study that 23andMe looked at was from Nordmark et al. The researchers looked at 1072 individuals of European descent and sequenced their genome at this one particular marker. They found that if the individual's genotype included a cytosine, that they were more likely to develop this disease. Since this individual has a cysteine in his genotype, he has a 1.7 times higher chance of developing this disease.
2. GG
At the marker rs7574865 in the gene STAT4, the individual's genotype is GG. The study that 23andMe looked at was from Korman et. al. They used the same basic principles as Nordmark did and found that if the individual's genotype included a thiamine, that they were more likely to develop this disease. This individual's genotype does not include thiamine. That means that this individual has normal odds of developing this syndrome.
Conclusions[]
In the end, John Burke should not be concerned about this one particular syndrome. 23andMe was not completely confident in its diagnosis (only given two star preliminary research). Even though he is over forty years old, he should just be aware of these symptoms and see if they develop or not.
Resources[]
1. John Burke's sequenced genome provided by 23andMe
2. "Sjögren's Syndrome", Sjögren's Syndrome Foundation, updated: 2014, accessed: 9/14/14
3. "Sjögren's Syndrome", U.S. National Library of Medicine provided by National Institute of Health (NIH).
4. Nordmark G et al. (2010). “Association of EBF1, FAM167A(C8orf13)-BLK and TNFSF4 gene variants with primary Sjögren's syndrome.” Genes Immun.
5. Korman BD et al. (2008) “Variant form of STAT4 is associated with primary Sjögren's syndrome.” Genes Immun 9(3):267-70.