3.9 years ago by
In general this is correct. The track you are examining will make a difference, but for a transcript/gene track such as RefSeq or Known Genes (aka most in the Gene and Gene Prediction group) this is true.
transcription start site = where transcription begins, include the 5' UTR
translation start side = where translation begins, meaning the start of coding region. generally within the first few exons and any particular gene will have many associated transcripts with alternates here, often with various changes in the UTR/promoter regions. This is part of genomic variation at a more macro level than say, a SNP. if the protein product is distinct, UCSC will keep the transcripts as individual variants.