XIRP2 and congenital myopathy: In addition, very recently a first case of a homozygous, recessive FLNC mutation (NM_001458.4:c.1325C > G; p.P442R) was reported to cause a severe congenital myopathy associated with degenerated myofibrils, advanced sarcomeric lesions and protein aggregates containing FLNc, Xin and XIRP2 in patient muscle fibers [40].