Phenotype and genotype in 101 males with X-linked creatine transporter deficiency.

Background: Creatine transporter deficiency is a monogenic cause of X-linked intellectual disability. Since its first description in 2001 several case reports have been published but an overview of phenotype, genotype and phenotype--genotype correlation has been lacking.

Methods: We performed a retrospective study of clinical, biochemical and molecular genetic data of 101 males with X-linked creatine transporter deficiency from 85 families with a pathogenic mutation in the creatine transporter gene (SLC6A8).

Prenatal testing for Huntington's disease in the Netherlands from 1998 to 2008.

This study aims to give an overview of the number of prenatal tests for Huntington's disease (HD), test results, and pregnancy outcomes in the Netherlands between 1998 and 2008 and to compare them with available data from the period 1987 to 1997. A total of 126 couples underwent prenatal diagnosis (PND) on 216 foetuses: 185 (86%) direct tests and 31 (14%) exclusion tests. In 9% of direct tests the risk for the foetus was 25%.

Breakpoint mapping of 13 large parkin deletions/duplications reveals an exon 4 deletion and an exon 7 duplication as founder mutations.

Early-onset Parkinson's disease (EOPD) has been associated with recessive mutations in parkin (PARK2). About half of the mutations found in parkin are genomic rearrangements, i.e.

Distinct genetic forms of frontotemporal dementia.

Background: Frontotemporal dementia (FTD) is the second most common type of presenile dementia and can be distinguished into various clinical variants. The identification of MAPT and GRN defects and the discovery of the TDP-43 protein in FTD have led to the classification of pathologic and genetic subtypes. In addition to these genetic subtypes, there exist familial forms of FTD with unknown genetic defects.

Diagnosis and management of early- and late-onset cerebellar ataxia.

Cerebellar ataxias represent a heterogeneous group of neurodegenerative disorders. Two main categories are distinguished: hereditary and sporadic ataxias. Sporadic ataxias may be symptomatic or idiopathic.