Ethical clearance was obtained from Institute Ethical Committee of Maulana Azad Medical College for this descriptive study conducted between July 2011 to September 2013. Every child with disproportionate short stature was subjected to detailed clinical and radiological evaluation. Clinical and radiological details were used to reach the most likely diagnosis with the help of London Dymorphology Database (LDB), Online Mendelian Inheritance in Man (OMIM), Atlas of Genetic Disorders of Skeletal Development, and online consultation with experts in the field of skeletal dysplasia. Cases, for which diagnosis was not made, were further submitted to panel of experts in European Skeletal Dysplasia Registry. Cases were further subjected for molecular analysis for confirming the diagnosis. Molecular diagnoses of all achondroplasia cases were done using a standard protocol [3]. Molecular testing in other cases was done based on hot spots in case of common mutation and gene sequencing in cases with multiple mutation.

We enrolled 40 cases (median age 3.1y; 24 males) in this study.Majority (35/40) presented with skeletal deformity. Web Table I shows phenotype of all cases: molecular diagnosis was possible in 18 of 40 cases. Achondroplasia was the commonest skeletal dysplasia, constituting 22.5 percent of the total cases enrolled in study. Genetic study of all Achondroplasia cases found c. 1138 G>A, p. Gly380Arg mutation in hot spot.

Achondroplasia as the commonest short limbed dwarfism has been previously reported [4, 5]. The mutation in achondroplasia as found in our study is also reported in earlier studies [6-8]. Most common short trunk dwarfism was Morquio syndrome. Genetic analysis of three cases revealed two pathogenic mutations in GALNS gene, which were also reported by Bidchol, et al. [9]. c.155C>T, p.Pro52Leu mutation was reported first time from India. Congenital hypothyroidism was found in five cases. Our study highlights that definitive diagnosis of skeletal dysplasia is possible with robust methodological approach. It helps in providing adequate risk of reoccurrence to families and charting adequate management plan.

Acknowledgement: Mr Avinash Lomash for doing molecular study of children with achondroplasia. This study was part of pool project approved by Council Scientific & Industrial Research (CSIR), New Delhi.

Contributors: AS: Recruited and diagnosed the patients, and drafted the manuscript. GP: searched literature and provided critical inputs in drafting the manuscript. RP & OPM: literature search, analysis of the data, and critical inputs to the manuscript. SK: conceptualized the study and helped in all stages of manuscript drafting.

Funding: None. Competing interest: None stated.

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