Cashmere is not merely goat hair.
No, no. Most hair on a goat—even a so-called cashmere goat—is coarse and thick, unsuitable for the neck of lady. Cashmere comes from a second undercoat that goats grow only in the winter, where the hairs are fine and soft and downy. But even goats specially bred to produce cashmere grow pitifully little—about half a pound per goat. Hence, your very expensive cashmere sweater. In China, the world’s top producer of cashmere, scientists have been trying to breed more productive cashmere goats. They’ve now used CRISPR, the genetic editing technique, to disrupt a single gene in cashmere goats. The change made hair in their undercoats even longer and more numerous—but not, crucially, any thicker. The genetic tweak boosts yield by about three ounces.