Floppy infant caused by MTM1 mutation: a first genetically-confirmed X-linked myotubular myopathy patient in Thailand.
Floppy infant syndrome (FIS) refers to a condition wherein an infant manifests generalized hypotonia since birth or in early life. It is heterogeneous and can be caused by various central nervous system disorders, neuromuscular diseases and genetic disorders. X-linked myotubular myopathy (XMTM) is a progressive congenital myopathy morphologically characterized by the presence of centrally placed nuclei in numerous muscle fibers without any other particular pathological abnormalities. Patients are frequently born with floppiness and respiratory distress. The vast majority of patients carry a truncating or missense mutation in MTM1. The authors report here a full term male baby with clinicopathological features of XMTM. The diagnosis is validated by the finding of a c. 141-144delAGAA mutation ofMTM1. To the best of the authors' knowledge, the present case is the first genetically confirmed XMTM in Thailand. A brief review of various neuromuscular disorders causing floppy infant syndrome is also included.
Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Teerin
T
Liewluck
Natte
N
Raksadawan
Chanin
C
Limwongse
Ichizo
I
Nishino
Tumtip
T
Sangruchi
D002874:Chromosome Mapping; D041321:Chromosomes, Human, X; D004252:DNA Mutational Analysis; D040181:Genetic Diseases, X-Linked / Q000175:diagnosis / Q000208:ethnology / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D020914:Myopathies, Structural, Congenital / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D010375:Pedigree; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D054558:Protein Tyrosine Phosphatases, Non-Receptor; D013785:Thailand
D017027:Protein Tyrosine Phosphatases; D054558:Protein Tyrosine Phosphatases, Non-Receptor; C099588:myotubularin