CALR and myasthenia gravis: In contrast, there are many well-known conditions for which autoantibody-related pathogenesis has been proven (by such natural experiments as neonatal disease induction through transplacental antibody passage): these include myasthenia gravis (acetylcholine receptor antibodies), Grave's disease (TSH-receptor stimulating antibodies), and SSA(Ro)-mediated neonatal lupus and congenital heart block.