Metachromatic leukodystrophy: identification of the first deletion in exon 1 and of nine novel point mutations in the arylsulfatase A gene.

Metachromatic leukodystrophy (MLD), a lysosomal storage disease caused by the deficiency of arylsulfatase A (ASA), is inherited as an autosomal recessive trait, and its frequency is estimated to be 1 in 40,000 live births. Genomic DNA from 21 MLD patients (14 late-infantile and 7 juvenile cases) was amplified in four overlapping PCR fragments and tested by allele-specific oligonucleotide (ASO) for the two common mutations 459 + 1G-->A and P426L. These mutations were found in only 28.6% of the alleles studied. The remaining alleles were analyzed by chemical mismatch cleavage (CMC) and automatic sequencing. In addition to five previously reported mutations (459 + 1G-->A, A212V, R244C, R390W, P426L), 10 novel mutations were identified: 9 missense mutations (S95N, G119R, D152Y, R244H, S250Y, A314T, R384C, R496H, K367N) and one 8 bp deletion in exon 1, the first mutation reported in this exon. These methods allowed us to identify 76% of the alleles tested. Genotype-phenotype correlations could be established for some of these mutations. These results confirm the heterogeneity of mutations causing MLD and suggest that CMC is a reliable and informative screening method for point mutation detection in the arylsulfatase A gene.

Gene delivery into the central nervous system by nasal instillation in rats.

Replication-deficient adenoviruses have been used successfully to transfer foreign DNA into postmitotic cells. This article demonstrates that it is possible to transfer the Escherichia coli lacZ gene in vivo into the central nervous system structures of rats after nasal instillation of replication-defective adenoviral vector AdRSV beta gal. Mitral cells from the olfactory bulb, neurons from the anterior olfactory nucleus, locus coeruleus and area postrema expressed beta-galactosidase for at least 12 days. No cytopathic effect was observed in the CNS structures studied at the viral titer used (1-3 x 10(9) plaque-forming units (p.f.u.)). This method could be useful for the gene therapy of diseases affecting different CNS structures.

Alternatives in human reproduction. Methods, indications, prognosis, bioethical problems.

The alternative methods in human reproduction do nothing else than try to help an individual or a couple to achieve the primordial goal of life: perpetuation of the species. These methods try to reconstruct the biologic premises necessary for perpetuation by various means such as: a. in vitro fecundation correlated or not with artificial fecundation with donor, ovocyte donation, embryo donation, borrowed mother; b. intratubular transfer of gametes; c. unnatural circumstances, i.e., the possibility that men be a host for the embryo up to term, a hypothesis which for the time being is possible only in science-fiction. The birth of Louisa Brown in 1978 was the border between hope and certainty, between dream and pragmatism. Thus, the alternative methods of reproduction have become routine in the medical life and penetrated into the conscience of an ever greater number of people but at the same time have raised an immense number of questions regarding the status of the embryo and the foetus, but more important, of the child born under these circumstances. These questions await answers both from medicine and the law and have to be within the limits of the common sense. Those who participate in the in vitro fecundation programs should not lose their quality of being human, should pay respect to the nature and the natural, encourage hope and be moral.