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An analysis of metaphase chromosomes of the scallop Hinnites distortus using Giemsa staining, chromosome measurements, silver staining, one- and two-color fluorescent in situ hybridization (FISH) ribosomal DNA (rDNA) probes and 4', 6-diamidino-2-phenylindole (DAPI) banding compatible with in situ hybridization is presented. The 5S rDNA show a conventional tandem arrangement with a repeat unit of about 450 bp and it maps at the pericentromeric region of the long arm of one subtelocentric pair.

The linkage analysis of pea comb (P), endogenous viral element (ev1), and blue eggshell loci (O) in chickens indicates that the three loci are placed in the order, centromere, P, ev1, and O on chromosome 1. The map distance between P and ev1 is between 2.5 to 5.7 cM in males and that between ev1 and O varies from 0.0 to 5.5 cM with an average of 4.0 cM. The average map distance between P and O loci is 4.1 cM. The analysis suggests that ev1 is on the shorter arm of chromosome 1 and is associated with the P and O loci.

Statistical analysis was done to evaluate the experimental findings on the genetic studies on fluctuating asymmetry (FA) for eight quasi-continuous (presence/absence) skeletal characters in randombred house mice. The results confirmed that variations in FA for the skeletal characters are largely due to environmental factors. The findings further indicated that there is no detectable additive genetic variance for FA.

Two genetic loci controlling the chlorimuron ethyl sensitivity (CS) have been identified in the soybean, Glycine max (L.) Merr., using a restriction fragment length polymorphism (RFLP) analysis. The F(sub 2) population from of PI 97100 X Coker 237 cross is used to construct a RFLP map, which includes 162 marker loci with an average distance of 10.7 cM and spans of about 1600 cM. A major locus is located on USDA linkage group E, which is 2.8 cM from cr168-1 toward cr274-1. The linkage group of the minor locus is unknown. The major locus accounts for 88% and the minor for 11% of the CS variations.

RFLP analysis of Phaseolus vulgaris crossbred with Phaseolus coccineus reveals that the selective transmission of P. vulgaris alleles in the crossbreed is due to the selection of certain individual chromosomes from the genome. The cDNA clone detects 165 F(sub 2) progenies of the crossbreed and maps them in the linkage map developed for the RFLP analysis. RFLP markers in the map prefer maternal transmission and reveal the F(sub 2) progeny to be homologous to histone H2A genes.

A study of diploid alfalfa using a microcomputer-based image analysis system for karyotyping enables alfalfa somatic chromosomes to become karyotypes. Autotetraploidy, the presence of several small-sized chromosomes, creates difficulty in karyotyping alfalfa somatic chromosomes. Autotetraploidy also produces obstruction in identifying eight sets of chromosomes. Pseudocolorizing the image of alfalfa chromosomes increases the edge distinguishing features and facilitates the development of new techniques for easier karyotyping.

A cytochrome b region is analysed using heteroduplex mobility assays (HMAs) with results comparable to those based on DNA sequences, including similar topologies with identical intrageneric, intraspecific and intergeneric relationships, in selected Callitrichids. HMA is sensitive enough to detect a 1-2% mismatch and can distinguish closely related species. HMAs can be used for detecting mismatches in the DNAs of different organisms, determining the genetic distances among them and constructing phylogenetic trees.

Restriction fragment length polymorphism (RFLP) analysis indicated genetic variation at the porcine submaxillary gland mucin (MUC) locus. A three-generation pedigree, having 10 founder individuals, 26 F1 animals and 200 F2 offspring indicated codominant inheritance. Linkage against a set of 56 genetic markers was examined. The mucin locus was assigned to a previously reported linkage group having the markers interferon gamma (IFNG), diacylglycerol kinase (DAGK) and an unknown microsatellite (S0092). The genes for mucin and interferon gamma were localized to porcine chromosome 5q2.3 and 5p1.2-q1.1 by using fluorescence and radioactive in situ hybridization, respectively, thus delegating four new markers to chromosome 5, which shares homologies with chromosome 5 in cattle and chromosome 12 in human beings.

A study was done on the genetic structure of ten Spanish dogs using comparative F statistics analysis. Electrophoretic data showed that 11 out of the 21 loci are polymorphic. Heterozygote deficit was measured to be 17% at the subpopulation, breed and ancenstral trunk levels. It was concluded that F statistics can be used for the analysis of the genetic structure of the Spanish dog populations and the reconstruction of phylogenies.

Determination of the genetic divergence within the blue and black South African wildbeests from the allozyme frequencies at 31 loci that code for proteins reveals the polymorphic presence of seven loci in the blue wildbeest and two variable loci in the black wildbeest. The black wildbeest exhibits 0.018 I 0.013 genetic variability while the blue wildbeest exhibits 0.091 plus or minus 0.030 variability. The interspecies genetic distance of 0.059 plus or minus 0.027, obtained from this study, matches the value obtained from mtDNA sequencing.

Mariner class of transposable elements, designated as Desmar1, are present in the genome of Hessian fly, Mayetiola destructor. Desmar1 has perfect inverted repeats and an open reading frame coding for transposase. The transposon is 1288 bp long and the inverted terminal repeats are of 28 bp. The open reading frame starts at nucleotide position 168, is 1041 bp long and terminates with GAA and TAA. Desmar1 shows similarity to Mos1 mariner element both at DNA and amino acid level. In situ hybridization with polytene chromosomes shows that it is predominantly present near the paracentromeric region.

Barley, Hordeum vulgare, has five phytochrome loci that form a multigene family. These are designated as phy1, phy2, phy3 and phy4. The loci phy4 is a duplicate loci present on burley chromosomes 2 and 7. The genes phy1, phy2 and phy3 are present on chromosomes 7,4 and 5, respectively. Linkage mapping, using wheat-burley addition line, locates phy1 and phy3 loci to the short arm of chromosome 7 and centromeric region of chromosome 5, respectively. All the five loci have two to three alleles. The genetic diversity values are between 0.1 and 0.74.

A microspore-derived callus culture population is used to construct a fractional linkage map for the sweet cherry, Prunus avium L. cultivar Emperor Francis. Seventy-nine random decanucleotide DNA primers and the polymerase chain reaction are used to genotype two allozymes and 90 random amplified polymorphic DNA (RAPD) markers. DNA blot and hybridization using five cloned RAPDs indicate that one of the decanucleotide primers amplifies a region of the Emperor Francis genome having a rare sequence and the other four amplify regions with repeated sequences.

Mutations in most of the 18 Dopa decarboxylase (Ddc) loci of Drosophila melanogaster produce similar cuticle and catecholamine-related disorders. Mutations in seven genes disturb catecholamine levels during pupal and prepupal development indicating that the genes probably encode proteins involved in catecholamine degradation. Mutations in 14 loci disturb cuticle formation, sclerotization or melanization, and mutations in 11 loci produce melanotic pseudotumors. The Ddc gene cluster is a large group of functionally related genes responsible for common physiological processes.

Linkage analysis of the oriental fruit fly, Bactrocera dorsalis showed three genetic markers associated with linkage groups. The mandarin red gene was associated with the matte gene while the white eye and amethyst loci were linked to the white purparium gene. The yellow eye was found to be related with the third linkage group. These findings are significant in the development of autocidal techniques for an effective sterile insect release method.

Phenetic and cladistic techniques used to observe the evolutionary relationships among 10 taxa of deer from the four genera of the subfamily Cervinae indicated that the genera of the Cervinal were not monophyletic. The genus Cervus was classified into two distinct groups with red deer, wapiti, Cervinal elaphus ssp; and Sika, Cervinal nippon; in one group, and sambar, Cervinal unicolor; and rusa Cervinae timorensis; in another. A close genetic relationship between the genus Elaphurus and the red deer, wapiti and sika group existed, while sambar and rusa were more similar to members of the genera Dama and Axis than to the other members of their own genus. The taxonomy of the species based on comparative morphology indicated fixed allelic differences between wapiti and rad, wapiti and sika and red and sika samples at three, six and seven loci, respectively.

Since humans first began to cultivate the soil, crops have been improved by selecting plants with desirable characteristics. More recently, crop improvement has involved interbreeding plant varieties or closely related [...]

A description is presented of the development and features of a Windows based Spatial Genetic Software computer program which can be used in the analysis of broad scale and local phenotypic and genetic structures.

There are several ways of carrying out genetic trait mapping. These methods determine the genetic distance between two loci on chromosome. Genetic markers are utilized to localize disease genes by linkage analysis. A critical component of a genetic marker is its heterozygosity that determines the proportion of individuals in a population who are heterozygous for that marker. A number of institutions offer free programs on genetic linkage analysis. In addition, there are also several books and Web sites on the subject.

A study was conducted to analyze DNA bands of dogs determined by the random amplified polymorphic DNA (RAPD) technique. A DNA template isolated from miniature poodles was utilized to carry out RAPD-polymerase chain reaction. Positive clones were then examined by restriction digestion. Experimental results indicated that RAPD bands amplified from the canine genome support more than one DNA fragment.

This study presents the findings of an analysis of evolutionary diagrams found in 31 biology textbooks for students ranging from middle school to the undergraduate level. Since the early 1990s, [...]

This book is a compendium of practitioner perspectives drawn from the rapidly evolving field of environmental information management. It is partitioned into seven sections comprising three to six papers each. [...]

Transcripts and their expression levels link an organism's genotype and phenotype, so understanding this relationship can aid our understanding of phenotypic evolution at the gene-expression level. The emerging field of [...]

The study results from a single-nucleotide polymorphism (SNP)-based analysis of canine diabetes mellitus (DM) in a diabetic cohort which identified 11, 10 haplotype associated with diabetes in the Cavalier King Charles Spaniel are reported.

A two-step comparative analysis is done to infer a canine chromosomal interval for localization of the chrUn genes by constructing a human-dog synteny map. Results reveal that dog chromosomal intervals for chrUn genes could be rapidly inferred using a reference species.

The genetic analysis of 192 unrelated individuals of an elite breeding population of Eucalyptus grandis (Hill ex Maiden) with a selected set of six highly polymorphic microsatellite markers developed for species of the genus Eucalyptus is reported. The high degree of multiallelism and the clear and simple codominant Mendelian inheritance of the set of microsatellites used provide a powerful system for uniquely identifying Eucalyptus individuals for fingerprinting purposes and parentage testing.

Research describing a graphical data analysis for the stability analysis of genotype x environment is presented. Both Tai's method and additive main effects and multiplicative interaction biplots are examined.

Reference strand-mediated conformation analysis is shown to be useful for examining canine immune responses. Nearly 1,400 dogs have been typed via this method; findings are discussed.

The aspects of PARENTE, an easy-to-do software package that carries out parentage analysis, using molecular data are put forth. The analysis and description of the program are described.