3MC Syndromes

Clinical Characteristics

Ocular Features:

The major ocular features involve the periocular structures. These result in the typical facial dysmorphism and include hypertelorism, blepharoptosis, blepharophimosis, and highly arched eyebrows. Ptosis, unilateral or bilateral, can be present.

One patient was reported to have unilateral aniridia and a corneal leucoma. Tear duct atresia was reported in another individual.

Systemic Features:

Systemic features are highly variable in their presence and severity. Facial clefting, growth deficiency, cognitive impairment, and hearing loss are present about half the time in some combination while craniosynostosis, urogenital anomalies, and radioulnar synostosis are seen in about a third of individuals. More rare features include cardiac defects and abdominal midline defects (omphalocele and diastasis recti).

Genetics

This condition (3MC) is now postulated to include at least 3 disorders (Malpuech-Michels-Mingarelli-Carnevale syndromes) and considered here as a single autosomal recessive disease complex with overlapping clinical features that requires genotyping for diagnostic separation. These are: 3MC1 syndrome (257920 [1]) resulting from homozygous mutations in the MASP1 [2] gene (3q27.3), 3MC2 syndrome (265050 [3]) caused by mutations in the COLEC11 [4] gene (2p25.3) and 3MC3 (248340 [5]) with mutations in the COLEC10 [6] gene (8q24.12).

Treatment

Treatment Options:

No effective general treatment has been reported.

References

Article Title:

COLEC10 is mutated in 3MC patients and regulates early craniofacial development [7]

Munye MM, Diaz-Font A, Ocaka L, Henriksen ML, Lees M, Brady A, Jenkins D, Morton J, Hansen SW, Bacchelli C, Beales PL, Hernandez-Hernandez V. COLEC10 is mutated in 3MC patients and regulates early craniofacial development. PLoS Genet. 2017 Mar 16;13(3):e1006679. doi: 10.1371/journal.pgen.1006679. eCollection 2017 Mar.

PubMed ID:

28301481

Mutations in lectin complement pathway genes COLEC11 and MASP1 cause 3MC syndrome [8]

Rooryck C, Diaz-Font A, Osborn DP, Chabchoub E, Hernandez-Hernandez V, Shamseldin H, Kenny J, Waters A, Jenkins D, Kaissi AA, Leal GF, Dallapiccola B, Carnevale F, Bitner-Glindzicz M, Lees M, Hennekam R, Stanier P, Burns AJ, Peeters H, Alkuraya FS, Beales PL. Mutations in lectin complement pathway genes COLEC11 and MASP1 cause 3MC syndrome. Nat Genet. 2011 Mar;43(3):197-203.

PubMed ID:

21258343

Michels syndrome, Carnevale syndrome, OSA syndrome, and Malpuech syndrome: variable expression of a single disorder (3MC syndrome) [9]

Titomanlio L, Bennaceur S, Bremond-Gignac D, Baumann C, Dupuy O, Verloes A. Michels syndrome, Carnevale syndrome, OSA syndrome, and Malpuech syndrome: variable expression of a single disorder (3MC syndrome)? Am J Med Genet A. 2005 Sep 1;137A(3):332-5. Review.

PubMed ID:

16096999

Apparent Malpuech syndrome: report on three Brazilian patients with additional signs [10]

Guion-Almeida ML. Apparent Malpuech syndrome: report on three Brazilian patients with additional signs. Am J Med Genet. 1995 Jul 31;58(1):13-7.

PubMed ID:

7573149