However, for TLR4 rs4986791, a significant increased PTB risk was found in Africans, and for TLR9 rs352139 a significant increased PTB </span>risk was found in Asians after subgroup analysis by ethnicity, although the enrolled studies were limited.
Polymorphisms rs3804099 (TLR2) and rs352139 (TLR9) may also be associated with PTB risk in the Moldavian population but their effect is less consistent across different studies.