Pitfalls in Genetic Diagnostics: Why Phenotyping is Essential

Abstract

New genetic testing technologies have revolutionized medicine within the past years. It is foreseeable that the development will continue with the introduction of new techniques. Nevertheless, despite improved technology, an exact clinical description of the phenotype is still necessary and it is important to critically question findings, both before initiating genetic testing and when interpreting the results. We present four brief case vignettes to point out difficulties associated with correctly interpreting genetic findings.

Keywords

next generation sequencing - phenotyping - inherited neurological diseases - muscular dystrophy - LBSL - rhombencephalosynapsis - GM1 gangliosidosis

Authors' Contributions

J.G.-A.: prepared the manuscript and clinically cared for cases 2, 3, and 4.

J.-C. S.-B.: prepared the manuscript and clinically cared for case 2.

E.B.: revised the manuscript and responsible for the magnetic resonance imaging findings in case 2.

T.H.: Revised the manuscript and was responsible for genetic diagnostics in case 2.

M.S.: revised the manuscript and clinically cared for case 4.

S.B.: revised the manuscript and was responsible for genetic diagnostics in cases 1 and 4.

F.F.: revised the manuscript and was responsible for the pathological assessment of the muscle biopsy in case 1.

I.S.: revised the manuscript and was responsible for the MRI findings in case 3.

H.H.: revised the manuscript comprehensively and clinically cared for cases 1, 2.

Ethics Approval and Consent to Participate and Consent for Publication

All patients were treated at university hospitals. The consent for treatment was signed by the parents at the outpatient presentation and for inpatient admission as part of the hospital formalities. This includes the consent for the publication of the medical data. For case 3, there is written consent from the parents to publish the photos with bars over the eyes.

Availability of Data and Material

The patient's findings and reports are documented in the electronical patient files.

Publication History

Received: 23 October 2020

Accepted: 27 January 2021

Article published online:
31 March 2021

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