The methods and compositions provided herein relate to the discovery of 13 STR markers, found on the human Y chromosome, having surprisingly high mutation rates when compared with 173 other Y-STR markers known today. The set of RM-Y-STRs may overcome the current dilemma of Y-chromosome analysis in forensic applications due to their extraordinary mutation properties. Embodiments of the invention include methods for allelic determination of rapidly-mutating Y-STR markers, amplification primers for the analysis of rapidly-mutating Y-STR markers, allelic ladders for analysis of rapidly-mutating Y-STR markers, and kits for the analysis of rapidly-mutating Y-STR markers.