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Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®

Spondylothoracic dysostosis

Reviewed February 2011

What is spondylothoracic dysostosis?

Spondylothoracic dysostosis is a condition characterized by the malformation of the bones of the spine and ribs. The bones of the spine (vertebrae) do not develop properly, which causes them to be misshapen and abnormally joined together (fused). The ribs are also fused at the part nearest the spine (posteriorly), which gives the rib cage its characteristic fan-like or "crab" appearance in x-rays. Affected individuals have short, rigid necks and short midsections because of the bone malformations. As a result, people with spondylothoracic dysostosis have short bodies but normal length arms and legs, called short-trunk dwarfism.

The spine and rib abnormalities cause other signs and symptoms of spondylothoracic dysostosis. Infants with this condition are born with a small chest that cannot expand adequately, often leading to life-threatening breathing problems. As the lungs expand, the narrow chest forces the muscle that separates the abdomen from the chest cavity (the diaphragm) down and the abdomen is pushed out. The increased pressure in the abdomen can cause a soft out-pouching around the lower abdomen (inguinal hernia) or belly-button (umbilical hernia).

Spondylothoracic dysostosis is sometimes called spondylocostal dysostosis, a similar condition with abnormalities of the spine and ribs. The two conditions have been grouped in the past, and both are referred to as Jarcho-Levin syndrome; however, they are now considered distinct conditions.

How common is spondylothoracic dysostosis?

Spondylothoracic dysostosis affects about one in 200,000 people worldwide. However, it is much more common in people of Puerto Rican ancestry, affecting approximately one in 12,000 people.

What genes are related to spondylothoracic dysostosis?

The MESP2 gene provides instructions for a protein that plays a critical role in the development of vertebrae. Specifically, it is involved in separating vertebrae from one another during early development, a process called somite segmentation. Mutations in the MESP2 gene prevent the production of any protein or lead to the production of an abnormally short, nonfunctional protein. When the MESP2 protein is nonfunctional or absent, somite segmentation does not occur properly, which results in the malformation and fusion of the bones of the spine and ribs seen in spondylothoracic dysostosis.

Related Gene(s)

Changes in this gene are associated with spondylothoracic dysostosis.

  • MESP2

How do people inherit spondylothoracic dysostosis?

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

Where can I find information about diagnosis or management of spondylothoracic dysostosis?

These resources address the diagnosis or management of spondylothoracic dysostosis and may include treatment providers.

  • Cleveland Clinic: Spine X-ray (
  • Gene Review: Spondylocostal Dysostosis, Autosomal Recessive (

You might also find information on the diagnosis or management of spondylothoracic dysostosis in Educational resources and Patient support.

General information about the diagnosis ( and management ( of genetic conditions is available in the Handbook.

To locate a healthcare provider, see How can I find a genetics professional in my area? ( in the Handbook.

Where can I find additional information about spondylothoracic dysostosis?

You may find the following resources about spondylothoracic dysostosis helpful. These materials are written for the general public.

You may also be interested in these resources, which are designed for healthcare professionals and researchers.

What other names do people use for spondylothoracic dysostosis?

  • Jarcho-Levin syndrome
  • STD

For more information about naming genetic conditions, see the Genetics Home Reference Condition Naming Guidelines ( and How are genetic conditions and genes named? ( in the Handbook.

What if I still have specific questions about spondylothoracic dysostosis?

Ask the Genetic and Rare Diseases Information Center (

What glossary definitions help with understanding spondylothoracic dysostosis?

autosomal ; autosomal recessive ; cell ; dwarfism ; gene ; hernia ; inguinal ; inherited ; malformation ; protein ; recessive ; syndrome ; x-rays

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.


  • Berdon WE, Lampl BS, Cornier AS, Ramirez N, Turnpenny PD, Vitale MG, Seimon LP, Cowles RA. Clinical and radiological distinction between spondylothoracic dysostosis (Lavy-Moseley syndrome) and spondylocostal dysostosis (Jarcho-Levin syndrome). Pediatr Radiol. 2011 Mar;41(3):384-8. doi: 10.1007/s00247-010-1928-8. Epub 2010 Dec 22. (
  • Cornier AS, Ramírez N, Arroyo S, Acevedo J, García L, Carlo S, Korf B. Phenotype characterization and natural history of spondylothoracic dysplasia syndrome: a series of 27 new cases. Am J Med Genet A. 2004 Jul 15;128A(2):120-6. (
  • Cornier AS, Staehling-Hampton K, Delventhal KM, Saga Y, Caubet JF, Sasaki N, Ellard S, Young E, Ramirez N, Carlo SE, Torres J, Emans JB, Turnpenny PD, Pourquié O. Mutations in the MESP2 gene cause spondylothoracic dysostosis/Jarcho-Levin syndrome. Am J Hum Genet. 2008 Jun;82(6):1334-41. doi: 10.1016/j.ajhg.2008.04.014. Epub 2008 May 15. (
  • Karnes PS, Day D, Berry SA, Pierpont ME. Jarcho-Levin syndrome: four new cases and classification of subtypes. Am J Med Genet. 1991 Sep 1;40(3):264-70. Review. (
  • Morimoto M, Takahashi Y, Endo M, Saga Y. The Mesp2 transcription factor establishes segmental borders by suppressing Notch activity. Nature. 2005 May 19;435(7040):354-9. (
  • Sasaki N, Kiso M, Kitagawa M, Saga Y. The repression of Notch signaling occurs via the destabilization of mastermind-like 1 by Mesp2 and is essential for somitogenesis. Development. 2011 Jan;138(1):55-64. doi: 10.1242/dev.055533. Epub 2010 Nov 23. (


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? ( in the Handbook.

Reviewed: February 2011
Published: February 1, 2016