Classification or Phylogenetic Estimates?

[m]3ta is a method that seeks to implement a taxic view of homology. The method is consistent with Patterson's tests for discriminating homology from nonhomology. Contrary to the claims of Kluge and Farris, (1999, Cladistics 15, 205–212), m3ta is not a phenetic method—nor does it necessarily place the basal split in a tree between the phenetically most divergent taxa. [m]3ta does not seek to accurately recover phylogeny but rather it seeks to maximize the information content of taxic homology propositions. [m]3ta is a method of classification in which the unit of analysis is the relation of homology. [m]3ta differs from all phylogenetic methods because the units of analyses in phylogenetic methods, including sca, are transformation series.     

A Founder Mutation in the GK1 Gene Is Responsible for Galactokinase Deficiency in Roma (Gypsies)

Galactokinase deficiency is an inborn error in the first step of galactose metabolism. Its major clinical manifestation is the development of cataracts in the first weeks of life. It has also been suggested that carriers of the deficiency are predisposed to presenile cataracts developing at age 20-50 years. Newborn screening data suggest that the gene frequency is very low worldwide but is higher among the Roma in Europe. Since the cloning of the galactokinase gene (GK1) in 1995, only two disease-causing mutations, both confined to single families, have been identified. Here we present the results of a study of six affected Romani families from Bulgaria, where index patients with galactokinase deficiency have been detected by the mass screening. Genetic linkage mapping placed the disease locus on 17q, and haplotype analysis revealed a small conserved region of homozygosity. Using radiation hybrid mapping, we have shown that GK1 is located in this region. The founder Romani mutation identified in this study is a single nucleotide substitution in GK1 resulting in the replacement of the conserved proline residue at amino acid position 28 with threonine (P28T). The P28T carrier rate in this endogamous population is approximately 5%, suggesting that the mutation may be an important cause of early childhood blindness in countries with a sizeable Roma minority.     

Long-term evolution and short-term adaptation of microbiota strains and sub-strains in mice

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Peptide immunocytochemistry in afferent neurons from lower gut in rats

Several peptides were detected in primary sensory neurons located in nodose and dorsal root ganglia and projecting from rat cecum and rectosigmoid, through a combination of retrograde staining by the fluorescent tracer DY-2HCl and of the immunofluorescent procedure of Coons. The three larger cell populations thus identified stored immunoreactive components respectively similar to calcitonin gene-related peptide (CGRP), substance P (SP), and a peptide related to peptide histidine methionine (PHM). The later immunoreactivity consisted of a single molecular form with an apparent molecular weight smaller than PHM itself. Fewer cells contained components immunologically similar to somatostatin 14 (ST14), to the 1-14 N-terminal sequence of somatostatin 28 (1-14 S28), and to neuropeptide Y (NPY). Neonatal treatment with capsaicin resulted in a drastic reduction of immunoreactivity for SP, PHM, ST14, 1-14 S28, and in a partial reduction of CGRP-like positive perikarya. These results demonstrate that several peptides are potentially involved in the sensory innervation of the lower gut in rat.