Can one gene make different proteins?

Higher organisms exhibit widespread alternative splicing, which is the inclusion and exclusion of specific exons and the use of alternative splice sites. The result is that a single gene can produce a large number of similar proteins, known as isoforms, each of which may have a distinct or different function. Many genes can therefore be understood as producing a family of protein isoforms rather than a single protein.

Certain viral genes use distinct ribosomal entry sites and frameshifting to alter the codon sequence in order to generate multiple proteins from a single RNA or DNA strand.

This page describes the ribosomal frameshift.

Yes, a single gene can produce multiple protein isoforms through a process known as alternative splicing. This process allows for the inclusion or exclusion of different combinations of exons within a gene from the final messenger RNA (mRNA) transcript.