Future work

From the findings of this study the following suggestions for future work are proposed:

 Reassessment of the phenotype of Family I might identify any clinical features that might be missed. With newly identified clinical assessment, another strategy of linkage analysis may be used to identify the causative genes. It may further enlighten the mode of inheritance and allows possible characterisation of disease associated variants.

 Target regions poorly covered in previous exome analysis of Family I to look for candidate genes that might be missed in the earlier exome sequencing analysis.

 Whole exome sequencing led to the discovery of novel mutations associated with different phenotypes of tooth agenesis. The new finding could be used to investigate the influence of those mutations on other teeth and other tissues or organs by studying their effect in transgenic mice.

 The clinical characterisation of the other 13 families could be extended to investigate the molecular basis of tooth agenesis in each family using whole exome sequencing. DNA was obtained from affected and unaffected members of those families. The discovery of novel mutations in those families could enhance knowledge about the molecular basis of tooth agenesis and lead to construction of a molecular classification of tooth agenesis.

 The initial study of tooth size in Family I has revealed significant reductions in tooth dimensions of several teeth. Future work on enlarged samples using the new three dimensional (3D) imaging and analysis technology may improve the study of penetration and expression of the mutations in the affected members and their relatives.

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