[2] His parents, Ray (Arlin), a textile worker, and Victor Altman, a grocer,[3] were Jewish[4] immigrants to Canada, each coming from Eastern Europe as a young adult, in the 1920s.

Altman's mother was from Białystok in Poland, and had come to Canada with her sister at the age of eighteen, learning English and working in a textile factory to earn money to bring the rest of their family to Quebec.

He was sponsored to come to Canada as a farm worker, but later, as a husband and a father of two sons, he supported the family by running a small grocery store in Montreal.

Due to personal concerns and the lack of opportunity for beginning graduate students to participate in laboratory work, he left the program without completing the degree.

Later, at the MRC Laboratory of Molecular Biology in Cambridge, England, Altman started the work that led to the discovery of RNase P and the enzymatic properties of the RNA subunit of that ribozyme.

While at Yale, Altman's Nobel Prize work came with the analysis of the catalytic properties of the ribozyme RNase P, a ribonucleoprotein particle consisting of both a structural RNA molecule and one (in prokaryotes) or more (in eukaryotes) proteins.