Is a microduplication of the long range SHH limb regulator ( ZRS ) associated with triphalangeal thumb-polysyndactyly syndrome?
A novel microduplication in 7q36.3 results in a similar TPT-PS phenotype as caused by single nucleotide alterations in the ZRS, the limb specific SHH regulatory element. Duplications can be added to the growing list of mechanisms that cause abnormalities of long range transcriptional control.
The wide variation in the analytical sensitivity of the primers used in the PCR, and the significant differences from the conventional method of ACL diagnosis found in this study, emphasize the importance of standardizing the PCR technique, analyzing sensitivity, and selecting suitable oligonucleotide primers.