Distribution of IFITM3 polymorphism (dbSNP: rs12252) in mestizo populations in four states of Mexico.

Interferon-inducible transmembrane protein 3 (IFITM3) participates in the defense against viral infections. This study identified and compared the frequency of the IFITM3 rs12252 polymorphism in 410 individuals in western Mexico. The western Mexican allelic frequencies (frequency of the "C" allele = 0.18) differ from some American, East Asian and European populations.

TNFR1-383 A˃C polymorphism association with clinical manifestations in primary Sjögren's syndrome patients.

Primary Sjögren's syndrome is an autoimmune disease affecting the function of exocrine glands. Tumor necrosis factor receptor-1 (TNFR1) is involved in apoptosis through extrinsic pathway initiation. The level of soluble TNFR1 is reported increased in rheumatoid arthritis, systemic lupus erythematosus, and primary Sjögren's syndrome patients. The TNFR1 gene contains a polymorphism that replaced an adenine with a cytosine at the -383 in promoter region position. The TNFR1-383 A˃C polymorphism has been associated with rheumatic diseases. We examined the association between the TNFR1-383 A˃C polymorphism and TNFR1 soluble (sTNFR1) levels and laboratory and clinical characteristics in primary Sjögren's syndrome patients. Eighty-two patients with primary Sjögren's syndrome classified using the American-European criteria and 84 healthy subjects were studied. Sjögren's Syndrome Disease Activity Index (SSDAI) and Sjögren's Syndrome Disease Damage Index were performed for all patients. Genotypic and allelic frequencies were similar in both groups (P = 0.317 and P = 0.329, respectively). sTNFR1 levels were similar in patients and healthy subjects (P = 0.051). High levels of C-reactive protein (P = 0.045) and rheumatoid factor (P = 0.040) in patients with the A˃C genotype were observed. In these patients, the SSDAI score was higher than in A˃A genotype carriers (P = 0.045). This is the first study that to examine the TNFR1-383 A˃C polymorphism in primary Sjögren's syndrome patients. Clinical parameters and SSDAI index were associated in A˃C genotype carriers. However, further studies with a larger sample are necessary to verify the association between primary Sjögren's syndrome and the TNFR1-383 A˃C polymorphism.

Pure 9p trisomy derived from a terminal balanced unreciprocal translocation.

The 9p trisomy is a relatively frequent disorder, while pure 9p trisomies are less frequent and usually derived from 9;22 translocations, duplications or 9p extra chromosomes. Here we report a patient with pure trisomy 9p derived from a terminal balanced unreciprocal translocation. The patient derived to the genetic service by psychomotor delay, presented at 2 years and 11 months: short stature, open anterior fontanelle, dysplastic ears, facial dysmorphisms, long and broad first toes with hypoplastic nails, central nervous system and skeletal alterations. The patient karyotype was: 46,XY,der(10)t(9;10) (p13.1;qter)mat while the mother karyotype was: 46,XX,t(9;10)(p13.1;qter). The presence of the subtelomeric region of 10q showed by FISH as well as the duplication of 9p subtelomere was further confirmed with multiplex ligation dependent probe amplification (MLPA) for the subtelomeric region of all chromosomes. The mechanism of formation seems to be due to a telomere break in 10q leading to loss of telomeric functions, permitting the 9p fusion; this has been supported with molecular probes showing telomere shortening in interstitial telomeric repeats, which are unable to prevent chromosome fusion. This is one of the few cases reported with terminal translocations (not jumping) preserving the subtelomeric region and highlights the importance of subtelomeric probes in terminal arrangements, and the utility of molecular probes, such as MLPA in defining this kind of abnormalities. In the clinical context, the patient presented a high proportion of 9p trisomy features which is expected considering the large 9p segment involved and the presence of the critical region 9p22.