MEN (General Swiss-German Mennonite)

Inheritance: autosomal recessive
Genes: unknown

Casamassima-Morton-Nance syndrome
CMN syndrome
Costovertebral dysplasia

Spondylothoracic dysplasia
Anomalous vertebrae
Anal atresia
Urogenital anomalies
Crab-like thorax
Rib fusion

Spondylocostal Dysostosis with Anal Atresia and Urogenital Anomalies

Clinical Characteristics

General description (for patients): 

Multiple congenital anomalies are found in this disorder, including those of the chest, ribs, urinary tract and anus.  The full extent of abnormalities is unknown as very few cases have been reported.  The head appears large relative to the chest at birth.

Medical description:  

This is an extremely rare disorder, one of several recessive syndromes known as spondylocostal dysostoses resembling Jarcho-Levin syndrome.  Anomalous development of ribs and vertebrae result in a characteristic ‘crab-like’ appearance of the thorax on X-ray.  Anal atresia and urogenital anomalous seem to be part of the syndrome. The ribs may be bifurcated and some are fused.  Congenital heart disease has been reported in some but not all cases.


Neither the inheritance mode nor the genetic defect are known.  Two male sibs born of a consanguineous Mennonite couple have been reported.  Other offspring of related parents have been reported suggesting autosomal recessive inheritance in at least some cases.  One reported patient carried a balanced translocation t[6;9][p12;q12].


The anal and some urogenital anomalies can be surgically corrected.  The same is true of the scoliosis.


Long term outlook unknown.  At least one infant has been stillborn.

Ancillary treatments and support:

General surgical and medical care as required for specific defects.

Specialists and specialty centers:

Surgeon, Urologist, Orthopedist.


Casamassima, C., Morton, C.C., Nance, W.E., Kodroff, M., Caldwell, R., Kelly, T., and Wolf, B.:  Spondylocostal dysostosis associated with anal and urogenital anomalies in a Mennonte sibship.  Am. J. Med. Genet. 8: 117-127, 1981.  PubMed ID: 7246601

Simpson, J.M., Cook, A., Fagg, N.L.K., MacLachlan, N.A., and Sharland, G.K.:  Congenital heart disease in spondylothoracic dysostosis: two familial cases.  J. Med. Genet. 32: 633-635, 1995.  PubMed ID: 7473656