CHRNA4 and Alzheimer disease: In addition, application of the nicotinic agonists [3H]epibatidine and [3H]nicotine, which bind with high affinity to subtypes of nAChR containing α4 and α3, respectively, either to members of the Swedish family carrying the 670/671 APP mutation (APPswe) or to sporadic cases of AD revealed less binding in various regions of the cortex [78].