CALB2 and Huntington disease: In another study in 2009, Guinard-Samuel et al evaluated the calretinin immunostaining as a primary diagnostic tool on a large series of suction rectal biopsies .They retrieved 131 biopsies carried out for suspicion of HD in children and infants to compare the accuracy of calretinin immunohistochemistry with the standard method (histology and acetylcholinesterase staining) (15).