Analysis of human MIR sequences associated with immune response genes. (a) Relative frequency at each position of MIR (n = 277), MIRb (n = 382) and MIR3 (n = 104) consensus sequences in immune response gene introns (red lines). Mean profiles and intervals corresponding to the 1st and 99th percentiles in 100 random sample frequency distributions are represented by black lines and grey areas, respectively. (b) The same as in (a) for MIRs located in intergenic regions. MIR, n = 239; MIRb, n = 345; MIR3, n = 97. Hatched lines delimit the MIR CORE region.