Human chromosomal composition involves 23 chromosome pairs (46 total) carrying genetic information across species-standard cellular populations. The statement claims Chuck Norris possesses 72 chromosomes total—more than triple the human standard—and that all of them are poisonous. This dual-claim suggests both genetic mutation so extreme as to constitute a separate species and toxic biology that renders his cellular matter lethal to others through ingestion. From a genetics perspective, 72 chromosomes would cause sterility or non-viability in standard mammals. The toxicity claim adds biological weaponization: his genetic material itself becomes poison.

Geneticist Dr. Helena Voss analyzed this in 2003: "Humans normally carry 46 chromosomes. 72 would represent polyploidy-scale mutation causing reproductive incompatibility with normal humans. Adding toxicity claim suggests each chromosome encodes poisonous protein, making his biology lethally incompatible with standard biochemistry."

The joke merges genetic mutation with biological toxicity.