From birth to maturity: midline tessier 0-14 craniofacial cleft patients who have completed protocol management at a single craniofacial unit

Introducing A Family With Tens of Rare Craniofacial Clefts

BACKGROUND

Craniofacial clefts are one of the rarest congenital malformations. When it comes to genetic inheritance patterns of craniofacial clefts, there are few studies on this subject due to the rarity and sporadic nature. In this study an extended family whose members have multiple craniofacial clefts has been introduced.

METHODS

The authors haphazardly found a family whose members have craniofacial clefts, either Tessier no. 0 or both Tessier nos. 0 and 14, and, consequently, they were categorized into 3 groups based on the severity of clefts.

RESULTS

Forty-two craniofacial clefts were noticed within the family. Twenty-two (52.3%) of patients were females and 20 (47.6%) were males. Twenty-three (54.8%) members had isolated Tessier no. 0 cleft, whereas 19 (45.2%) members had both Tessier nos. 0 and 14. Of all 42 patients, 18 (42.8%), 3 (7.1%), and 21 (50%) patients had severe, intermediate, and mild clefts, respectively.

CONCLUSION

The present study reveals that in some patients genetic background is likely to be the cause of clefts.

Functional analysis of SPECC1L in craniofacial development and oblique facial cleft pathogenesis

BACKGROUND

Oblique facial clefts, also known as Tessier clefts, are severe orofacial clefts, the genetic basis of which is poorly understood. Human genetics studies revealed that disruption in SPECC1L resulted in oblique facial clefts, demonstrating that oblique facial cleft malformation has a genetic basis. An important step toward innovation in treatment of oblique facial clefts would be improved understanding of its genetic pathogenesis. The authors exploit the zebrafish model to elucidate the function of SPECC1L by studying its homolog, specc1lb.

METHODS

Gene and protein expression analysis was carried out by reverse-transcriptase polymerase chain reaction and immunohistochemistry staining. Morpholino knockdown, mRNA rescue, lineage tracing and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assays were performed for functional analysis.

RESULTS

Expression of specc1lb was detected in epithelia juxtaposed to chondrocytes. Knockdown of specc1lb resulted in bilateral clefts between median and lateral elements of the ethmoid plate, structures analogous to the frontonasal process and the paired maxillary processes. Lineage tracing analysis revealed that cranial neural crest cells contributing to the frontonasal prominence failed to integrate with the maxillary prominence populations. Cells contributing to lower jaw structures were able to migrate to their destined pharyngeal segment but failed to converge to form mandibular elements.

CONCLUSIONS

These results demonstrate that specc1lb is required for integration of frontonasal and maxillary elements and convergence of mandibular prominences. The authors confirm the role of SPECC1L in orofacial cleft pathogenesis in the first animal model of Tessier cleft, providing morphogenetic insight into the mechanisms of normal craniofacial development and oblique facial cleft pathogenesis.