Basic concepts on dysmorphology 2012

Author: F. Forzano
Submitted: Tuesday 26th of June 2012 02:44:01 PM
Submitted by: egf
Language: English
Content type: Learning resource
Educational levels: expert, qc2, qc3

Abstract

The term “Dysmorphology” has been coined by Dr. David W. Smith in the 1960's to generally define the study of human congenital malformations, particularly those affecting the “morphology” (anatomy) of the individual. A few years later, Dr. Jon Aase, a former Dr Smith’s student, elaborated much more this concept and stated that "As a scientific discipline, Dysmorphology combines concepts, knowledge, and techniques from the fields of embryology, clinical genetics and pediatrics. As a medical subspecialty, dysmorphology deals with people who have congenital abnormalities and with their families." The clinical examination of the morphology of referred patients has proved essential for the delineation of hundreds of syndromes and has been a key tool for the discovery of many “disease genes”. A structural defect is in fact an inborn error in morphogenesis, and the study of these anomalies ultimately lead to an extended knowledge on genetic mechanisms which regulate normal embryonal development too. The dysmorphological assessment relies on a careful analysis of congenital anomalies. While major malformations are obvious at birth and usually lead to a prompt referral for a medical evaluation, minor malformations have no clinical consequences and can easily be neglected. However, the recognition of these minor malformations might be the essential clue for the detection of a genetic condition, which can allow to establish the more appropriate intervention for the child and the whole family. Since the evaluation of minor malformation is largely subjective, new computer-based 3D techniques have recently being developed to analyse facial features in an objective, operator-independent way and to assist clinical training in pattern recognition. Databases like OMIM, London Medical Databases, Possum are useful tools commonly used by dysmorphologists to achieve a diagnosis in difficult cases. With the introduction of new cytogenetic and molecular testing, the traditional path from phenotype to genotype in dysmorphology has now become a two-way road. In fact large scale testing of patients with developmental problems has brought to the identification of several ‘new’ microdeletion/duplication syndromes through so called ‘reverse dysmorphology’, that is, using a genotype to phenotype approach. The combination of all these new tools and techniques makes Dysmorphology nowadays a very exciting and dynamic branch of Clinical Genetics. The parallel improvement in both phenotyping and genotyping and their continuous reciprocal interaction will ultimately lead to a profound knowledge on pathogenesis of a number of diseases and also on physiological development and functioning.

Preview

Learning packages

This resource is part of the following learning package:

Similar resources


Loading ...

Download

Original version - English

abstract FORZANO_Basic_concepts_in_dysmorphology_Ronzano_2012_april_6_STUDENTS_5189.pdf

IMS Metadata

Citation

F. Forzano. Basic concepts on dysmorphology 2012. EUROGENE portal. June 2012. online: http://eurogene.open.ac.uk/content/basic-concepts-dysmorphology-2012

Rating

0

Terms of use

This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License. Read more.

sfy39587f01