The 2022 reference genome version produced by the T2T Consortium was T2T-CHM13.
The Telomere-to-Telomere Consortium published the assembly in 2022, addressing large regions that earlier human reference assemblies could not resolve. Those missing regions included centromeres, telomeres, repetitive DNA, and the short arms of five chromosomes. The initial complete assembly is commonly identified as T2T-CHM13v1.1.
CHM13 refers to the complete hydatidiform mole cell line used as the source. Because this material has effectively one copy of the relevant genome sequence, it helped researchers assemble difficult regions without the complications of two divergent parental chromosome copies. “T2T” means telomere-to-telomere.
This was not simply a rename of GRCh38, hg19, or NCBI Build 36. Those are earlier or separate reference assemblies used widely in genomics. T2T-CHM13 added nearly 200 million base pairs and supplied a much more complete map, although later work has continued to improve reference resources and represent human diversity through pangenomes.