[The contribution of molecular genetics to the nosology and diagnosis of neurological disorders of childhood].
BACKGROUND
The recent spectacular development of molecular genetics has considerably amplified the role of genetics in classification and diagnosis, especially in degenerative diseases but also in other conditions such as developmental brain disorders and predisposition to some acquired diseases (e.g. infections and immunological maladies).


OBJECTIVE
The aim of this article is not to review the ever growing list of disorders due to gene abnormalities but to present a few reflections on their consequences and to try to assess their impact on some of the basic concepts in clinical medicine.


METHODS
The main advantages attributable to the use of molecular genetics are the identification of clinical conditions with different clinical phenomena and due to a single cause and vice versa the existence of clinical conditions in which many different genetic abnormalities can be found. Its main drawbacks derive from its application for establishing nosologic classifications only on the basis of its findings, mainly due to the lack of congruence between phenotype and genotype.


CONCLUSIONS
The information from molecular biology should be integrated with that of other sources in a significant profile, which is the intellectual basis of clinical medicine.
Aicardi
J
J
Servicio de Neurología Pediátrica y de Enfermedades Metabólicas, Hospital Robert Debré París, Francia.
D002869:Chromosome Aberrations / Q000235:genetics; D025063:Chromosome Disorders; D003937:Diagnosis, Differential; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008967:Molecular Biology; D010641:Phenotype; D017354:Point Mutation / Q000235:genetics; D013132:Spinocerebellar Degenerations / Q000175:diagnosis* / Q000235:genetics*; D014960:X Chromosome / Q000235:genetics