[5][6] Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion.

They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed.

Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA.

Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology.

This article on a gene on human chromosome 6 is a stub.