Muscular dystrophy-dystroglycanopathies (MDDGs) resulting from fukutin-related protein (<i>FKRP</i>) gene mutations are rare disorders that result in a wide spectrum of clinical severity based on the age of onset, the degree of myogenic atrophy, and/or neurologic involvement.
FKRP mutations account for a broad spectrum of patients with muscular dystrophy, from a severe congenital form with or without mental retardation (MDC1C) to a much milder limb-girdle muscular dystrophy (LGMD2I).
FKRP mutations account for a broad spectrum of patients with muscular dystrophy, from a severe congenital form with or without mental retardation (MDC1C) to a much milder limb-girdle muscular dystrophy (LGMD2I).
Fukutin-related protein (FKRP) muscular dystrophy (n=6) was the most common diagnosis, followed by anoctaminopathy-5 (n=3), calpainopathy-3 (n=2) and dystrophinopathy (n=2).
Allelic mutations in putative glycosyltransferase genes, fukutin and fukutin-related protein (fkrp), lead to a wide range of muscular dystrophies associated with hypoglycosylation of α-dystroglycan, commonly referred to as dystroglycanopathies.
Downregulating FKRP expression in zebrafish by two different morpholinos resulted in embryos which had developmental defects similar to those observed in human muscular dystrophies associated with mutations in FKRP.
Dystroglycan is a protein which binds directly to two proteins defective in muscular dystrophies (dystrophin and laminin alpha2) and whose own aberrant post-translational modification is the common aetiological route of neuromuscular diseases associated with mutations in genes encoding at least six other proteins (POMT1, POMT2, POMGnT1, LARGE, FKTN and FKRP).
Limb girdle muscular dystrophy type 2I (LGMD2I) is an autosomal recessive muscular dystrophy that is rare in Asia and is caused by mutations in the fukutin-related protein gene (<i>FKRP</i>).
Mutations in the fukutin-related protein gene account for a broad spectrum of phenotypes ranging from severe congenital muscular dystrophies to a much milder limb-girdle muscular dystrophy 2I.
Of the cases where the CAPN3 gene was not affected, approximately 20% were diagnosed as LGMD2Imuscular dystrophy, while facioscapulohumeral muscular dystrophy (FSHD) was uncommon in this sample.
Other genes (POMT1, POMGnT1, fukutin, and FKRP) that encode known or putative glycosylation enzymes are also causally associated with human congenital muscular dystrophies.
The results demonstrate that tamoxifen and raloxifene hold significant potential for treating FKRP-related muscular dystrophy and probably other muscular dystrophies.
There is a marked variation in clinical phenotypes that have been associated with mutations in FKRP, ranging from severe congenital muscular dystrophies to limb-girdle muscular dystrophy type 2I (LGMD2I).