Little Differences Show Up Big in Gene Expression

Little Differences Show Up Big in Gene Expression

“And though she be but little, she is fierce.”
A Midsummer Night’s Dream, I, ii, 335

I am what some of my friends affectionately call “vertically challenged.” The sun visor in my car is often useless to me and, depending on the chair, my feet don’t always lie flat on the floor. Several of my coworkers at RTB share these trials with me—but though we are short, we hope to help make a big difference in the lives of people RTB reaches.

Likewise, though there is a possible 98–99% genetic similarity between humans and chimps, it’s the little variations that seem to make big differences. As researchers dig deeper into genetic comparisons, a more complex picture emerges.

Biochemist and RTB visiting scholar Patricia Fanning points to FOXP2, a gene heavily involved in controlling human language capabilities, as an example of the “subtle elegance” that underlies the uniqueness of human biology.

Humans alone carry a unique version of FOXP2 that is foundational to humanity’s advanced written and spoken language abilities. The human FOXP2 differs from the chimp FOXP2 by two nucleotides and from the mouse FOXP2 by three. The two nucleotide changes in the human FOXP2 result in two amino acid changes in its protein. Those changes dramatically alter the DNA binding activity of FOXP2. These alternations are essential to humanity’s extraordinary language capabilities.

Biochemist Fazale Rana also frequently reports on research that demonstrates the vital genetic differences between humans and other primates. In an upcoming TNRTB article about research on induced pluripotent stem cells from chimps and humans, he writes that there is “growing recognition that gene expression is the key to understanding the biological and behavioral uniqueness of humans.”

All these little differences add up to big factors in favor of a creation model explanation, which posits that a Creator used similar blueprints (genes) to construct different creatures as He saw fit.

— Maureen

Resources: There are plenty of resources, such as articles and podcasts, on the comparisons of chimp and human DNA to explore on the RTB website. Good places to start include the RTB 101 page on this issue and Humans vs. Chimps topic page.