Toll Like Receptor 6 is a member of the Toll-like receptor (TLR) family which plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from Drosophila to humans and share structural and functional similarities. By screening a human placenta library with a mouse Tlr6 probe, Takeuchi et al. (1999) isolated a cDNA encoding human TLR6. The deduced 796-amino acid type I transmembrane protein, which is 74% identical to mouse Tlr6 and 69% identical to TLR1, contains an N-terminal signal peptide, 20 tandemly repeated extracellular leucine-rich motifs, and a cytoplasmic domain homologous to IL1R, as seen in other TLRs. RT-PCR analysis detected Tlr6 in mouse thymus, spleen, ovary, and lung.