# What's the difference between VCF spec versions 4.1 and 4.2?

What are the key differences between VCF versions 4.1 and 4.2? It looks like v4.3 contains a changelog (specs available here) but earlier specifications do not.

This biostar post points out one difference: the introduction of Number=R for fields with one value per allele including REF — can anyone enumerate the other changes between these two versions?

This is easy to check, you can download both specs in .tex format and do diff.
2. INFO field can have one value for each possible allele (code R).
4. Alternate base (ALT) can include *: missing due to a upstream deletion.