Autosomal dominant familial spastic paraplegia (FSP) is a genetically heterogeneous neurodegenerative disorder displaying anticipation for which three loci have been mapped to the chromosomal positions 14q11.2-q24.3 (SPG3), 2p21-p24 (SPG4) and 15q11.1 (SPG6). The repeat expansion detection (RED) method has been used to demonstrate expanded CAG repeats in some FSP families that map to SPG4. We analyzed 20 FSP families, including four for which there is evidence for linkage to SPG4, and found that in most cases the repeat expansion detected by RED is due to non-pathogenic expansions of the chromosome 18q21.1 SEF2-1 or 17q21.3 ERDA1 locus. Polymorphic expansions at SEF2-1 and ERDA1 appear frequent and may confound RED studies in the search for genes causing disorders demonstrating anticipation. In six FSP families, however, CAG repeat expansion was detected in a subset of affected and at-risk individuals that did not result from expansion of the SEF2-1 and ERDA1 loci. Overall, 11 of 37 (30%) of the FSP patients with a CAG/CTG repeat expansion are unaccounted for by the SEF2-1 and ERDA1 loci, compared with two of 23 (9%) of the unaffected at-risk individuals and none of 19 controls. In the majority of cases these novel expansions were shorter than those previously reported.

Lymphoid cells from virgin, untreated BALB/c mice cultured 5 days on 12- or 13-day syngeneic mouse embryo fibroblasts (MEF) or on cells from a syngeneic 3-methylcholanthrene-induced mouse sarcoma (1315) were cytotoxic for 1315 tumor target cells when tested with a microcytotoxicity assay. They did not kill embryo or skin fibroblast target cells. Lymphoid cells cultured with 11-, 14- or 17-day MEF were not cytotoxic for cells from the 1315 tumor, from embryo or from adult skin. Lymphoid cells from multiparous BALB/c mice cultured on 11-, 12- or 13-day MEF, on line 1315 sarcoma cells or on skin fibroblasts were cytotoxic for tumor target cells. MEF were killed by multipara lymphoid cells that had been cultured on 11-, 12- or 13-day MEF or on the 1315 tumor line. Multipara lymphoid cells cultured on 1315 cells or 12-day MEF were cytotoxic for adult skin fibroblasts, while multipara lymphoid cells cultured on 14- or 15-day MEF were not cytotoxic for any of the target cells. The data thus indicate that lymphoid cells can mediate both primary and secondary immune reaction in vitro to antigens shared by neoplastic and normal embryonic cells, and that the primary reactions appear to be more specific to putatively embryonic tumor antigen(s) than the secondary ones.

We present a genome assembly from an individual Limnephilus marmoratus (a caddisfly; Arthropoda; Insecta; Trichoptera; Limnephilidae). The genome sequence is 1,630 megabases in span. Most of the assembly (99.93%) is scaffolded into 30 chromosomal pseudomolecules, including the assembled Z sex chromosome. The mitochondrial genome has also been assembled and is 15.4 kilobases in length.

The molecular characterisation of the dystrophin gene, mutations in which are responsible for X linked Duchenne