In the nocturnin and angel family, the drosophila and human genes share one intron position.

This is especially, though not exclusively, true of genes within the same species, because genes within one species frequently share cells with one another.

Co-regulated genes may share similar expression profiles, maybe involved in related functions or regulated by common regulatory elements [ 14].

These genes share similar structure and sequence.

Their genes are grouped in operons, genes within operons share a common promoter unit.

These genes share close identity with the bacterial deaminases involved in nucleotide metabolism.

Because genes in the two branches never share the same bodies, they may drift apart until genes from the two branches become incompatible.

It is believed that co-regulated genes share similar promoters and/or are involved in similar biological processes [ 1].

Estimates show that erythroid cells express at least 4,000 genes, so many genes are obliged to seek out and share the same factory.

The two genes are found on opposite DNA strands and share a 5' region which is where they are thought to have an antisense interaction.