Each immunoglobulin<unk><unk>  molecule contains approximately 220 amino acids in a single polypeptide<unk>  that is folded to form constant and variable region domains. Each domain comprises two β-pleated sheets. The sheets are linked by a disulfide bridge and together form a roughly barrel-shaped structure known as a β-barrel. The variable (V) domain of<unk><unk> s has a high degree of structural diversity, particularly the antigen-binding region. In addition, the first 23 amino acids of the 1st variable domain framework region have a number of variations known as subgroups. Four kappa (Vκ1–Vκ4) and six lambda subgroups (Vλ1–Vλ6) can be identified. The specific subgroup structures influence the potential of the<unk><unk><unk> s to polymerise such that AL amyloidosis is associated with Vλ6 and<unk><unk>  deposition disease with Vκ1 and Vκ4.
Serum free light-chain measurement
Bone biopsy
Serum protein electrophoresis
Renal biopsy
Skin biopsy
Scanning laser ophthalmoscopy
Retinoscopy
Urine protein/creatinine ratio