Novel MASP1 mutations are associated with an expanded phenotype in 3MC1 syndrome

Küçük Resim Yok

Tarih

2015

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

BioMed Central Ltd.

Erişim Hakkı

info:eu-repo/semantics/openAccess

Özet

Background: 3MC1 syndrome is a rare autosomal recessive disorder characterized by intellectual disability, short stature and distinct craniofacial, umbilical, and sacral anomalies. Five mutations in MASP1, encoding lectin complement pathway enzymes MASP-1 and MASP-3, have thus far been reported to cause 3MC1 syndrome. Only one previously reported mutation affects both MASP-1 and MASP-3, while the other mutations affect only MASP-3. Methods: We evaluated six unrelated individuals with 3MC1 syndrome and performed Sanger sequencing for all coding exons of MASP1. We also measured complement lectin and alternative pathway activities in an affected individual's serum. Results: We found two novel splice site mutations, c.1012-2A?>?G in one and c.891?+?1G?>?T in two probands, and three novel missense mutations, c.1451G?>?A (p.G484E), c.1657G?>?A (p.D553N), and c.1987G?>?T (p.D663Y). Missense mutations affect only MASP-3, while splice site mutations affect both MASP-1 and MASP-3. In a proband who is homozygous for c.891?+?1G?>?T, we detected a total lack of lectin complement pathway activity and a 2.5-fold lower alternative pathway activity. The phenotype observed in patients whose both MASP-1 and MASP-3 are affected and in those whose only MASP-3 is affected does not appear to be different. We observed structural brain abnormalities, neonatal tooth, a vascular anomaly and a solid lesion in liver as novel phenotypic features of 3MC1 syndrome. Conclusion: Novel mutations and additional phenotypic features expand the genotypic and phenotypic spectrum of 3MC1 syndrome. Although patients with MASP-1 dysfunction in addition to disrupted MASP-3 have an altered complement system, their disease phenotype is not different from those having only MASP-3 dysfunction. © 2015 Atik et al.

Açıklama

Anahtar Kelimeler

3MC syndrome, Complement, Lectin pathway, MASP-1, MASP-3

Kaynak

Orphanet Journal of Rare Diseases

WoS Q Değeri

Scopus Q Değeri

Q1

Cilt

10

Sayı

1

Künye