The present invention relates to a mutant reverse transcriptase (RT) with increased thermal stability relative to the wildtype, a nucleic acid encoding the mutant RT, a cell comprising the mutant RT or the nucleic acid, a kit comprising the mutant RT, the use of the mutant RT for cDNA synthesis, method for reverse transcription of RNA comprising synthesizing cDNA with the use of the mutant RT and a method for detecting an RNA marker in a sample with the use of the mutant RT.