(updated January 2017)
Beginning in 1990, more than 1990 sequences of the gene were reported and ultimately deposited in the international DNA databases. The rate of deposition of DNA sequences for the 56 kDA TSA gene is shown in the figure below (through December 2017):
There is considerable variation in the size of sequences that have been reported in various studies. The size distribution of the sequences deposited in the DNA databases is given in the figure below (through December 2017):
Sequences that exceed 1300 bases in length include the majority of the protein coding gene region, and almost all of these longer sequences include all of the four variable regions of the protein. These variable regions of the protein correspond to the most highly variable portions of the gene.
In December 2017, there were 401 sequences that exceeded 1300 nucleotides in length, and these provide the most accurate set from which to derive a classification of sequence types or sequence clades for the 56 kDa TSA gene.