An unusual neurological syndrome of crawling gait, dystonia, pyramidal signs, and limited speech

Background: The purpose of the study was to identify and molecularly characterize a neurological syndrome in a consanguineous Pakistani family. 

Methods: Five patients, their 2 siblings, and their parents were clinically examined. DNA from all 7 siblings was genotyped with Affymetrix SNP arrays and sequencing of selected candidate genes. 

Results:: An unusual neurological syndrome of crawling gait, predominant leg dystonia, pyramidal signs, microcephaly, and suspected deafness segregated in the family. Three patients ambulated on hands and knees, either by hopping and crossing their legs, or by dragging the legs behind them. Two patients have acquired the ability to walk bipedally with a dystonic gait. Unexpectedly, no chromosomal region was homozygous in patients only. Under different disease models, we localized 7 chromosomal regions in the genome common to all patients. No pathogenic mutations were identified in selected candidate genes or the mitochondrial genome. 

Conclusion:: We describe an unusual movement disorder syndrome reminiscent of but distinct from Uner Tan syndrome.