The study describes the link between serum levels of surfactant protein D, its genetic polymorphisms and risk of Chronic Obstructive Pulmonary Disease. Single nucleotide polymorphisms has been genotyped using PCR and restriction analysis. Serum SP-D levels were measured using a specific immunoassay. Autoantibodies including anti dsDNA, antinuclear and antinucleosome antibodies levels were also recorded. It was found that allele 'A' at rs3088308 (p=0.000, B=-0.399) and 'C' allele at rs721917 (p=0.021; B=-0.344) were associated with significantly low serum SP-D levels. Additionally allele 'T'...