Methodology: -: a single seed-based sampling strategy for marker-assisted selection in rice.

Background: Integrated breeding approaches such as combining marker-assisted selection and rapid line fixation through single-seed-descent, can effectively increase the frequency of desirable alleles in a breeding program and increase the rate of genetic gain for quantitative traits by shortening the breeding cycle. However, with most genotyping being outsourced to 3rd party service providers' nowadays, sampling has become the bottleneck for many breeding programs. While seed-chipping as prevailed as an automatable seed sampling protocol in many species, the symmetry of rice seeds makes this solution as laborious and costly as sampling leaf tissue.

Silica exposure among male current smokers is associated with a high risk of developing ACPA-positive rheumatoid arthritis.

Objective: To study the association between silica exposure, separately as well as combined with smoking, and the risk of developing rheumatoid arthritis (RA) with or without the presence of antibodies against citrullinated peptide antigens (ACPA).

Methods: This Swedish population based case-control study analysed 577 incident RA cases and 659 randomly selected controls, all men aged 18-70 years, included during May 1996 to May 2006. Self-reported silica exposure, defined as exposure to stone dust, rock drilling or stone crushing and cigarette smoking was registered.

A new model for an etiology of rheumatoid arthritis: smoking may trigger HLA-DR (shared epitope)-restricted immune reactions to autoantigens modified by citrullination.

Objective: To investigate whether smoking and HLA-DR shared epitope (SE) genes may interact in triggering immune reactions to citrulline-modified proteins.

Methods: In a case-control study involving patients with recent-onset rheumatoid arthritis (RA), we studied interactions between a major environmental risk factor (smoking), major susceptibility genes included in the SE of HLA-DR, and the presence of the most specific autoimmunity known for RA (i.e.

A gene-environment interaction between smoking and shared epitope genes in HLA-DR provides a high risk of seropositive rheumatoid arthritis.

Objective: The main genetic risk factor for rheumatoid arthritis (RA) is the shared epitope (SE) of HLA-DR, while smoking is an important environmental risk factor. We studied a potential gene-environment interaction between SE genes and smoking in the etiology of the 2 major subgroups of RA: rheumatoid factor (RF)-seropositive and RF-seronegative disease.

Methods: A population-based case-control study involving incident cases of RF-seropositive and RF-seronegative RA (858 cases and 1,048 controls) was performed in Sweden.