[Phenotypic variability of the 1q21.1 microdeletion syndrome in members of the same family: relevance of detection of neuropsychiatric disorders for diagnosis of genetic syndromes].

INTRODUCTION

1q21.1 microdeletion syndrome is a caused by a recurrent deletion of the 1q21.1 copy-number variant, which spans 800 kb and includes at least seven genes. It is associated with a variable phenotype. Neuropsychiatric abnormalities have been previously described in many of the previously reported cases, but its true prevalence is unknown.

AIM: To illustrate the phenotypic variability in 1q21.1 microdeletion syndrome.

CASE REPORTS: Four individuals of the same kindred harboring a 1.74-Mb deletion within 1q21.1 are included. In our patients a heterogeneous phenotype is recognized. Neuropsychiatric disorders or more specifically impulse control disorders were common to all the four cases that we present.

CONCLUSIONS

1q21.1 microdeletion syndrome is phenotypically heterogeneous even among members of the same family. Behavioral or neuropsychiatric abnormalities are frequent. Paucisymptomatic forms with individuals presenting exclusively psychiatric disorders have been identified.