Investigating the etiology of multiple tooth agenesis in three sisters with severe oligodontia.
OBJECTIVE
To describe the dentofacial phenotypes of three sisters with severe non-syndromic oligodontia, to report on the mutation analysis in three genes, previously shown to cause various phenotypes of non-syndromic oligodontia and in two other suspected genes. Based on the phenotypes in the pedigree of this family, the different possible patterns of transmission are discussed.


METHODS
Anamnestic data and a panoramic radiograph were taken to study the phenotype of the three sisters and their first-degree relatives. Blood samples were also taken to obtain their karyotypes and DNA samples. Mutational screening was performed for the MSX1, PAX9, AXIN2, DLX1 and DLX2 genes.


RESULTS
The probands' pedigree showed evidence for a recessive or multifactorial inheritance pattern. Normal chromosomal karyotypes were found and - despite the severe oligodontia present in all three sisters - no mutation appeared to be present in the five genes studied so far in these patients.


CONCLUSIONS
In the three sisters reported, their common oligodontia phenotype is not caused by mutations in the coding regions of MSX1, PAX9, AXIN2, DLX1 or DLX2 genes, but genetic factors most probably play a role as all three sisters were affected. Environmental and epigenetic factors as well as genes regulating odontogenesis need further in vivo and in vitro investigation to explain the phenotypic heterogeneity and to increase our understanding of the odontogenic processes.
Swinnen
S
S
Department of Orthodontics, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Catholic University Leuven, Leuven, Belgium.
Bailleul-Forestier
I
I
Arte
S
S
Nieminen
P
P
Devriendt
K
K
Carels
C
C
D000848:Anodontia / Q000097:blood / Q000000981:diagnostic imaging / Q000235:genetics*; D030161:Avian Proteins / Q000097:blood / Q000235:genetics; D060466:Axin Protein; D002648:Child; D002675:Child, Preschool; D003598:Cytoskeletal Proteins / Q000097:blood / Q000235:genetics; D005260:Female; D005838:Genotype; D018398:Homeodomain Proteins / Q000097:blood / Q000235:genetics; D006801:Humans; D007621:Karyotyping / Q000379:methods; D051957:MSX1 Transcription Factor / Q000097:blood / Q000235:genetics; D051764:PAX9 Transcription Factor / Q000097:blood / Q000235:genetics; D010641:Phenotype; D011859:Radiography; D035781:Siblings; D014071:Tooth Abnormalities / Q000097:blood / Q000000981:diagnostic imaging / Q000235:genetics*; D014157:Transcription Factors / Q000097:blood / Q000235:genetics
C491761:AXIN2 protein, human; D030161:Avian Proteins; D060466:Axin Protein; D003598:Cytoskeletal Proteins; C088334:Distal-less homeobox proteins; D018398:Homeodomain Proteins; D051957:MSX1 Transcription Factor; D051764:PAX9 Transcription Factor; C497323:PAX9 protein, human; D014157:Transcription Factors; C071559:Hbox 7 protein, Gallus gallus