monilethrix

monilethrix /mōnil′əthriks/ [L, monile necklace; Gk, thrix, hair] , an autosomal-dominant condition in which the hairs exhibit multiple constrictions, with a beading effect, and are brittle, rarely reaching an inch in length before breaking.

Individual with monilethrix. Arrow highlights the area of constriction (Rudnicka et al, 2013)