Novel mutations in Myoclonin1/EFHC1 in sporadic and familial juvenile myoclonic epilepsy

BACKGROUND

Juvenile myoclonic epilepsy (JME) accounts for 3 to 12% of all epilepsies. In 2004, the GENESS Consortium demonstrated four missense mutations in Myoclonin1/EFHC1 of chromosome 6p12.1 segregating in 20% of Hispanic families with JME.

OBJECTIVE

To examine what percentage of consecutive JME clinic cases have mutations in Myoclonin1/EFHC1.

METHODS

We screened 44 consecutive patients from Mexico and Honduras and 67 patients from Japan using heteroduplex analysis and direct sequencing.

RESULTS

We found five novel mutations in transcripts A and B of Myoclonin1/EFHC1. Two novel heterozygous missense mutations (c.755C>A and c.1523C>G) in transcript A occurred in both a singleton from Mexico and another singleton from Japan. A deletion/frameshift (C.789del.AV264fsx280) in transcript B was present in a mother and daughter from Mexico. A nonsense mutation (c.829C>T) in transcript B segregated in four clinically and seven epileptiform-EEG affected members of a large Honduran family. The same nonsense mutation (c.829C>T) occurred as a de novo mutation in a sporadic case. Finally, we found a three-base deletion (-364--362del.GAT) in the promoter region in a family from Japan.

CONCLUSION

Nine percent of consecutive juvenile myoclonic epilepsy cases from Mexico and Honduras clinics and 3% of clinic patients from Japan carry mutations in Myoclonin1/EFCH1. These results represent the highest number and percentage of mutations found for a juvenile myoclonic epilepsy causing gene of any population group.

Degenerative ultrastructural changes observed in the neuropil of caudate nuclei from Parkinson's disease patients

Degenerative changes of the pars compacta of the substantia nigra are considered the main physiopathological basis of Parkinson's disease, while most authors believe that the neostriatum is well preserved in these cases. This paper deals with the preliminary ultrastructural observations made in the neuropil of the caudate nucleus of Parkinson's disease patients. We have observed (1) astrocytic proliferation, neuronal degeneration, degenerated axons, and hyperdense postsynaptic neurites (dendrites), and (2) that degenerative patterns vary from one case to another. Physiopathological and therapeutical implications are discussed.

Multidisciplinary analysis of the effectiveness of autologous neural transplant (adrenal medulla) as treatment of Parkinson's disease

The neurobiological aspects of human neural transplants are far from being understood. We have approached their study by means of a multidisciplinary working team. Nine patients with Parkinson's disease were subjected to open brain surgery for grafting of autologous adrenal medulla. Not all patients improved. Those patients that did so showed different patterns of improvement. Rigidity was the sign most relieved in this group of patients. Electroencephalographic changes were attributable to surgical manipulation. High-performance liquid chromatographic quantification of catecholaminergic metabolites did not correlate with post-grafting outcome. Biopterin levels showed a significant increment after surgery. More interdisciplinary studies ought to be done on neural transplants.