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1.
Published gene frequency data, checked for consistency of allele definitions across laboratories and for comparability of
geographically identical samples, were pooled into a data set containing frequencies at nine loci for each of 20 populations
that encompassed 10 macaque species. Genetic distances were calculated by the methods of Kidd and Cavalli-Sforza (1974). These
distances were used to construct phylogenetic trees and to evaluate the relationships between divergence times and effective
population sizes. Inter-and intraspecific genetic distances and the groupings defined by phenetic tree analyses support Fooden’s
(1976) classification of the genus Macacainto four species groups. A paleozoogeographical model of Asia including the known times of major sea-level changes allows
us to explain Macacainto four species groups. A paleozoogeographical model of Asia including the known times of major sea-level changes allows
us to explain qualitatively the inferred evolutionary relationships among macaque species. Many assumptions are required in
order to estimate the variables necessary in the quantitative prediction of genetic differences for a comparison between any
two populations. Examination of those assumptions demonstrates the need for more accurate genetic as well as paleozoogeographic
information.
An erratum to this article is available at . 相似文献
2.
3.
A linkage group of five DNA markers on human chromosome 10 总被引:3,自引:0,他引:3
Five chromosome 10 DNA markers (D10S1, D10S3, D10S4, D10S5, and RBP3) were typed in five large pedigrees with multiple endocrine neoplasia type 2A (MEN-2A) and in five non-MEN-2A pedigrees. Linkage analyses showed that these loci and the locus for MEN-2A (MEN2A) are in one linkage group spanning at least 70 cM. The order of the marker loci is RBP3-D10S5-D10S3-D10S1-D10S4, with interlocus recombination frequencies of 7, 13-19, 19, and 19%, respectively, all on the same side of MEN2A. Analyses of sex-specific recombination frequencies indicated no significant differences between males and females for any of the map intervals studied. Previous localization of D10S5 and RBP3 to the proximal region of the long arm and the pericentric region, respectively, comparison of results with other studies, and our preliminary results with other chromosome 10 markers suggest that the D10S4 end of the map extends into the long arm. Our linkage map has been constructed using only two- and three-locus analyses. It will be possible to combine our results with those of other groups to construct a more detailed and accurate genetic map of chromosome 10. 相似文献
4.
5.
Identification by molecular cloning of two forms of the alpha-subunit of the human liver stimulatory (GS) regulatory component of adenylyl cyclase 总被引:10,自引:0,他引:10
Two DNA molecules complementary to human liver mRNA coding for the alpha-subunit of the stimulatory regulatory component Gs of adenylyl cyclase were cloned. One of the two forms is a full-length cDNA of 1614 nucleotides plus a poly(A) tail of 59 nucleotides. The deduced sequence of 394 amino acids encoded by its open reading frame is essentially identical to that of the alpha-subunits of Gs identified by molecular cloning from bovine adrenals, bovine brain and rat brain. Two independent clones of the other type of cDNA were isolated. Both were incomplete, beginning within the open reading frame coding for the alpha s polypeptide. One codes for amino acids 5 through 394 and the other for amino acids 48 through 394 of the above described cDNA of 1614 nucleotides, and both have the identical 3'-untranslated sequence. They differ from the first cDNA, however, in that they lack a stretch of 42 nucleotides (numbers 214 through 255) and have nucleotides 213 (G) and 256 (G) replaced with C and A, respectively. This results in a predicted amino acid composition of another alpha-subunit of Gs that is shorter by 14 amino acids and contains two substitutions (Asp for Glu and Ser for Gly) at the interface between the deletion and the unchanged sequence. We call the smaller subunit alpha s1 and the larger alpha s2. This is the first demonstration of a structural heterogeneity in alpha s subunits that is due to a difference in amino acid sequence. 相似文献
6.
OBJECTIVE--To determine the extent of maternal morbidity associated with in utero transfer. DESIGN--Retrospective study of 190 consecutive cases over two years. SETTING--Liverpool Maternity Hospital. PATIENTS--190 Pregnant women were transferred to the hospital under the in utero transfer arrangements from district general hospitals both within and outside the Mersey region. The women admitted were divided into two categories: those in threatened or established uncomplicated preterm labour and those who may or may not have been in threatened or established preterm labour but who had coexisting complicating factors affecting the mother or fetus, or both. INTERVENTIONS--Planned delivery of the fetus if indicated and arrangements for appropriate postpartum care of the mother. MAIN OUTCOME MEASURE--Assessment of the progress of labour and, if appropriate, resuscitation of the mother. RESULTS--Women who were transferred with no coexisting disease (124) had relatively uncomplicated deliveries whereas those transferred with coexisting diseases (66) exhibited considerable morbidity and 17 of these required prolonged intensive monitoring after delivery. CONCLUSIONS--In utero transfer in healthy mothers may have benefits for babies born very prematurely. If mothers have coexisting disease, however, the desirability of transfer should be reviewed urgently in the light of the considerable maternal morbidity associated with these problems. In these cases transfer may introduce an additional hazard. 相似文献
7.
Borrelia burgdorferi is a spirochete pathogen transmitted among warm-
blooded hosts by ixodid ticks. Frequency-dependent selection for variant
outer-surface proteins might be expected to arise in this species, since
rare variants are more likely to avoid immune surveillance in previously
infected hosts. We sequenced the OspA and OspB genes of nine North American
strains and compared them with nine strains previously described. For each
gene, the mean number of synonymous substitutions per synonymous site and
the mean number of nonsynonymous substitutions per nonsynonymous site show
only a twofold excess of silent mutations. Synonymous rates vary widely
along the OspB protein. Some regions show a significant excess of silent
substitutions, while divergence in other regions is constrained by biased
base composition or selection. The presence, in antigenically important
regions of the protein, of significant variation among strains, as well as
evidence for recombination among strains, should be considered in attempts
to develop vaccines against this disease.
相似文献
8.
M P ROBINSON G BUTCHER R H CURTIS K G DA VIES K EVANS 《The Annals of applied biology》1993,123(2):337-347
Two monoclonal antibodies, which differentially recognise the two species of potato cyst nematodes (PCN), Globodera pallida and G. rostochiensis, are described. They have been shown to have potential for quantification of these two species, recognising proteins of the same molecular weight (34 kD) in both species. Further investigation showed these proteins to have isoelectric points at pH values of 5.7 in G. pallida and 5.9 in G. rostochiensis, in common with the proteins used by Fleming & Marks (1983) to differentiate the species of PCN. They are likely to be structurally very similar, with the same physiological function (and therefore similar concentrations) in the two species. In cross-reactivity tests with a wide range of soil nematode species, the antibodies reacted strongly only with species of the genus Globodera, and thereby confirmed their potential as the basis of a quantitative immunoassay likely to be useful in management of PCN populations. 相似文献
9.
10.
Abnormalities in monoamine metabolism, including serotonin metabolism, have been implicated in the pathophysiology of affective disorders, schizophrenia, suicide, and other psychiatric disorders. Serotonin transporter protein (SERT) allows neurons to retrieve serotonin that has been released into a synapse. SERT is a site of action for several drugs with CMS effects, including both therapeutic agents (e.g., antidepressants) and drugs of abuse (e.g., cocaine). This gene had previously been physically mapped to chromosome 17. We used a PCR product corresponding to the 3 untranslated region of the gene as a probe to identify restriction fragment length polymorphism (RFLP), which we then used to establish that the SLC6A4, genetic locus for SERT, is near 17q12 and probably flanked by D17S58 and D17S73 (a location consistent with observed crossovers). These data should be useful for linkage studies of neuropsychiatric disorders. (Joyce et al. 1993). Neurotransmitter reuptake sites (including also the norepinephrine transporter protein and the dopamine transporter protein) are logical candidate genes for susceptibility to psychiatric illness. We have previously (Gelernter et al. 1993) mapped the norepinephrine transporter protein to chromosome 16q21. We describe here linkage mapping of the serotonin transporter protein gene (gene symbol SLC6A4, for solute carrier family 6 (neurotransporter, serotonin), member 4), which was cloned in 1991 (Blakely et al. 1991; Hoffman et al. 1991) and previously assigned to chromosome 17, most likely to band 17q11.2, by in situ hybridization (Ramamoorthy et al. 1993). Our linkage results confirm the initial mapping of SLC6A4 and place it in the linkage map of proximal 17q. 相似文献