IF and IHC techniques can additionally occasionally result in nonspecific trapping of circulating plasma proteins, resulting in false-positive results for AL.11 Although there are available antibodies that can reliably type precursor proteins for some types of hereditary amyloid (serum AA [SAA], ATTR, fibrinogen Aα-chain), there are currently no available antibodies to certain forms of hereditary amyloid.11 When the CR stain is equivocal, EM can demonstrate presence of amyloid, characterized by nonbranching, randomly arranged fibrils measuring 7–12 nm in diameter. The gene discussed is TTR; the disease is amyloidosis.