Elements of morphology: Standard terminology for the trunk and limbs

Abnormal dental phenotypes in GAPO syndrome: A descriptive study with a new ANTXR1 variant & insights on teeth eruption

Objective

GAPO syndrome is usually diagnosed clinically owing to its characteristic features of growth retardation, alopecia, pseudoanodontia, and ophthalmic anomalies. Pseudoanodontia describes the failure of eruption of the two sets of teeth in these patients. Thus, the abnormal dental phenotype is the emergence of a set or part of a set of dentitions.

Purpose

This study reports the physical, oro-dental, and molecular findings of two new sibs with GAPO syndrome and provides a description of the dental phenotype of one of the patients reported before.

Materials & Methods

The patients were subjected to full medical history taking and three generations-pedigree construction. They were phenotyped according to the elements of morphology: Standard terminology series. After parental consents were acquired, molecular analysis was carried out for the two sibs (Patient 1 & 2).

Results

These included a new gene variant associated with erupted teeth in GAPO syndrome and new clinical features. A new classification for the terminologies of eruption disturbances was suggested.

Conclusion

The study asserts the importance of oro-dental examination and follow-ups as dental updates may occur in these cases.

Enhancing Molecular Testing for Effective Delivery of Actionable Gene Diagnostics

There is a deep need to navigate within our genomic data to find, understand and pave the way for disease-specific treatments, as the clinical diagnostic journey provides only limited guidance. The human genome is enclosed in every nucleated cell, and yet at the single-cell resolution many unanswered questions remain, as most of the sequencing techniques use a bulk approach. Therefore, heterogeneity, mosaicism and many complex structural variants remain partially uncovered. As a conceptual approach, nanopore-based sequencing holds the promise of being a single-molecule-based, long-read and high-resolution technique, with the ability of uncovering the nucleic acid sequence and methylation almost in real time. A key limiting factor of current clinical genetics is the deciphering of key disease-causing genomic sequences. As the technological revolution is expanding regarding genetic data, the interpretation of genotype-phenotype correlations should be made with fine caution, as more and more evidence points toward the presence of more than one pathogenic variant acting together as a result of intergenic interplay in the background of a certain phenotype observed in a patient. This is in conjunction with the observation that many inheritable disorders manifest in a phenotypic spectrum, even in an intra-familial way. In the present review, we summarized the relevant data on nanopore sequencing regarding clinical genomics as well as highlighted the importance and content of pre-test and post-test genetic counselling, yielding a complex approach to phenotype-driven molecular diagnosis. This should significantly lower the time-to-right diagnosis as well lower the time required to complete a currently incomplete genotype-phenotype axis, which will boost the chance of establishing a new actionable diagnosis followed by therapeutical approach.