Mhk Ho

Population differences in SLE susceptibility genes: STAT4 and BLK, but not PXK, are associated with systemic lupus erythematosus in Hong Kong Chinese.

In this study, we compared the association of several newly discovered susceptibility genes for systemic lupus erythematosus (SLE) between populations of European origin and two Asian populations. Using 910 SLE patients and 1440 healthy controls from Chinese living in Hong Kong, and 278 SLE patients and 383 controls in Thailand, we studied association of STAT4, BLK and PXK with the disease. Our data confirmed association of STAT4 (rs7574865, odds ratio (OR) =1.71, P=3.55 × 10−23) and BLK (rs13277113, OR=0.77, P=1.34 × 10−5) with SLE. It was showed that rs7574865 of STAT4 is also linked to hematologic disorders and potentially some other subphenotypes of the disease. More than one genetic variant in STAT4 were found to be associated with the disease independently in our populations (rs7601754, OR=0.59, P=1.39 × 10−9, and P=0.00034 when controlling the effect of rs7574865). With the same set of samples, however, our study did not detect any significant disease association for PXK, a risk factor for populations of European origin (rs6445975, joint P=0.36, OR=1.06, 95% confidence interval: 0.93–1.21). Our study indicates that some of the susceptibility genes for this disease may be population specific.

Association of BANK1 and TNFSF4 with systemic lupus erythematosus in Hong Kong Chinese

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. Recently, single nucleotide polymorphisms (SNPs) in BANK1 and TNFSF4 have been shown to be associated with SLE in Caucasian populations, but it is not known whether they are also involved in the disease in other ethnic groups. Recent data from our genome-wide association study (GWAS) for 314 SLE cases and 920 controls collected in Hong Kong identified SNPs in and around BANK1 and TNFSF4 to be associated with SLE risk. On the basis of the results of the reported studies and our GWAS, SNPs were selected for further genotyping in 949 SLE patients (overlapping with the 314 cases in our GWAS) and non-overlapping 1042 healthy controls. We confirmed the associations of BANK1 and TNFSF4 with SLE in Chinese (BANK1, rs3733197, odds ratio (OR)=0.84, P=0.021; BANK1, rs17266594, OR=0.61, P=4.67 × 10−9; TNFSF4, rs844648, OR=1.22, P=2.47 × 10−3; TNFSF4, rs2205960, OR=1.30, P=2.41 × 10−4). Another SNP located in intron 1 of BANK1, rs4522865, was separately replicated by Sequenom in 360 cases and 360 controls and was also confirmed to be associated with SLE (OR=0.725, P=2.93 × 10−3). Logistic regression analysis showed that rs3733197 (A383T in ankyrin domain) and rs17266594 (a branch point-site SNP) from BANK1 had independent contributions towards the disease association (P=0.037 and 6.63 × 10−8, respectively). In TNFSF4, rs2205960 was associated with SLE independently from the effect of rs844648 (P=6.26 × 10−3), but not vice versa (P=0.55). These findings suggest that multiple independent genetic variants may be present within the gene locus, which exert their effects on SLE pathogenesis through different mechanisms.

Association of CD247 with systemic lupus erythematosus in Asian populations

Objective: Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. CD247 (CD3Z, TCRZ) plays a vital role in antigen recognition and signal transduction in antigen-specific immune responses, and is known to be involved in SLE pathogenesis. Weak disease association was reported for genetic variants in this gene in Caucasian studies for SLE, Crohns disease and systemic sclerosis, but its role as a genetic risk factor was never firmly established. Methods: In this study, using a collection of 612 SLE patients and 2193 controls of Chinese ethnicity living in Hong Kong in a genome-wide study, single nucleotide polymorphisms (SNPs) in and around CD247 were identified as being associated with SLE. The two most significant SNPs in this locus were selected for further replication using TaqMan genotyping assay in 3339 Asian patients from Hong Kong, Mainland China, and Thailand, as well as 4737 ethnically and geographically matched controls. Results: The association of CD247 with SLE in Asian populations was confirmed (rs704853: odds ratio [OR] = 0. 81, p = 2.47 × 10−7; rs858543: OR = 1.10, p = 0.0048). Patient-only analysis suggested that rs704853 is also linked to oral ulcers, hematologic disorders and anti-double-stranded DNA (dsDNA) antibody production. Conclusion: A significant association between variants in CD247 and SLE was demonstrated in Asian populations. Understanding the involvement of CD247 in SLE may shed new light on disease mechanisms and development of new treatment paradigms.

Two missense variants in UHRF1BP1 are independently associated with systemic lupus erythematosus in Hong Kong Chinese

UHRF1BP1 encodes a highly conserved protein with unknown function. Previously, a coding variant in this gene was found to be associated with systemic lupus erythematosus (SLE) in populations of European ancestry (rs11755393, R454Q, P=2.22 × 10−8, odds ratio=1.17). In this study, by a combination of genome-wide study and replication involving a total of 1230 patients and 3144 controls, we confirmed the association of this coding variant to SLE in Hong Kong Chinese. We also identified another coding variant in this gene that independently contributes to SLE susceptibility (rs13205210, M1098T, P=4.44 × 10−9, odds ratio=1.49). Cross-population confirmation establishes the involvement of this locus in SLE and indicates that distinct alleles are contributing to disease susceptibility.

The genetics of macrocephaly, autistic spectrum disorders and developmental delay in Chinese children

M. Tamulaitiene, M. Jaramaviciene, J. Jaramavicius, V. Alekna. Faculty of Medicine of Vilnius University, Vilnius, Lithuania Objectives: To analyze the methods of treatment and outcome of hip fractures in Lithuania. Methods: This population-based retrospective study was performed collecting the data from all orthopaedic inpatient departments in Lithuania. The records of subjects, who were hospitalized because of primary hip fracture (ICD-10 codes S72.0, S72.1 and S72.2) at the age over 40 years in 2010, were examined. Methods of treatment were conservative and surgical, while the latter was divided into fixation by screws, plate or intramedullary nail (IN), and total hip arthroplasty (TA). The outcomes included death, transfer to another department, discharge home or long-term hospital, and rehabilitation. Results: In 2010, 2626 hip fractures occurred in Lithuania. The most common method used was osteosynthesis: fixation by plate accounted for 41.4%, screw – 21.1%), and by IN – in 3.4% of cases. TAwas used in 25.9% and conservative treatment – in 8.1% of patients. After fixation by screws, plates and IN, the majority of patients were discharged home (42.5%, 35.8% and 37.8%, respectively) or to long-term care hospital (24.5%, 22% and 32.2%, respectively). Otherwise, after TA, 70.1% of patients underwent rehabilitation. Among patients treated conservatively, 39.7% were transferred to another department, ant their mortality rate was highest (4.2%). Number of deaths was lowest after treatment with screws (0.7%). Conclusion: In 2010, in Lithuania, the majority of patients with hip fracture were treated with osteosynthesis using the external fixation. Rehabilitation was more often outcome of treatment using total hip arthroplasty, as compared to osteosynthesis.