Check out our New Publishers' Select for Free Articles

Biochemical Genetics (v.49, #11-12)

Genetic Structure of Marchalina hellenica (Hemiptera: Margarodidae) Populations from Turkey: Preliminary mtDNA Sequencing Data by Maria Bouga; Vasiliki Evangelou; Dimitris Lykoudis; Ibrahim Cakmak; Fani Hatjina (pp. 683-694).

The scale insect Marchalina hellenica (Gennadius) (Hemiptera: Margarodidae) contributes to the production of pine honey in Turkey and Greece via the honeydew excreted when it feeds on pine trees. Although it is an insect of prime economic importance, there is no information on its genetic structure. Preliminary data were obtained based on sequencing analysis of 12s rDNA and COI mtDNA gene segments from samples from four areas of Turkey. Sequences of the 12s rDNA gene segment from Greek samples available in GenBank were also included. No variability was detected concerning the COI mtDNA gene segment analysis, although 13 haplotypes were revealed based on the 12s rDNA gene segment. The most distant population was from Mudanya-Bursa Province (Turkey). Further research is necessary on the genetic structure and variability of M. hellenica populations from the two neighboring countries.

Keywords: Marchalina hellenica ; Turkey; mtDNA; Genetic structure; Sequencing

An Efficient DNA Extraction Method for Desert Calligonum Species by Raoudha Abdellaoui; Hassen Gouja; Amel Sayah; Mohamed Neffati (pp. 695-703).

Genetic conservation programs in arid environments rely on molecular methods for diversity assessments. DNA-based molecular profiling will aid in conservation and protection of species from genetic erosion. Obtaining intact genomic DNA from Calligonum species, of sufficiently high-quality that is readily amplifiable using PCR, is challenging because of the presence of the exceptionally large amount of oxidized polyphenolic compounds, polysaccharides, and other secondary metabolites. The present method involves a modification of the available CTAB method employing higher concentrations of NaCl and CTAB, and incorporating PEG 6000 (1%) and glucose. The yield of DNA was 60–670 μg g⁻¹ of fresh tissue. The protocol has been tested with two species from the arid region. The DNA isolated was successfully amplified by two ITS primer pairs. PCR-RFLP analysis of the ITS1-5.8S-ITS2 region among and within Calligonum species followed by sequencing is under way.

Keywords: Calligonum species; DNA extraction; PCR; ITS1-5.8S-ITS2 region

Gender-Specific Association Between ACE Gene I/D Polymorphism and Blood Pressure Response to Hydrochlorothiazide in Han Chinese Hypertensive Patients by Yun Li; Peng Yang; Shouling Wu; Juxiang Yuan; Chong Shen; Ying Wu; Dandan Zhao; Qi Ren; Fumin Feng; Weijun Guan (pp. 704-714).

To evaluate the interaction between the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and gender with individual blood pressure response to hydrochlorothiazide (HCTZ) in hypertensives, we enrolled 829 mild-moderate hypertensive patients. All subjects were given HCTZ (12.5 mg) orally each day for 6 weeks. A total of 776 patients completed the study. There was statistically significant interaction between the effects of genotype and gender on systolic (P = 0.002) and diastolic (P = 0.048) response after adjusting for covariables. Moreover, in each gender, the genotype that was associated with the greatest blood pressure response to HCTZ (DD homozygotes in men and II homozygotes in women) was also associated with the greatest increase in serum ACE activity in response to HCTZ. The results suggest that the I/D polymorphism of the ACE gene is associated with interindividual differences in the blood pressure response to a low dose of a diuretic in a gender-specific manner in the Han Chinese population with hypertension.

Keywords: Hypertension; ACE gene; Polymorphism; Diuretic; Gender

Genetic Variability and Differentiation Among Populations of the Azorean Endemic Gymnosperm Juniperus brevifolia: Baseline Information for a Conservation and Restoration Perspective by Luís Silva; Rui B. Elias; Mónica Moura; Harald Meimberg; Eduardo Dias (pp. 715-734).

The Azorean endemic gymnosperm Juniperus brevifolia (Seub.) Antoine is a top priority species for conservation in Macaronesia, based on its ecological significance in natural plant communities. To evaluate genetic variability and differentiation among J. brevifolia populations from the Azorean archipelago, we studied 15 ISSR and 15 RAPD markers in 178 individuals from 18 populations. The average number of polymorphic bands per population was 65 for both ISSR and RAPD. The majority of genetic variability was found within populations and among populations within islands, and this partitioning of variability was confirmed by AMOVA. The large majority of population pairwise F _ST values were above 0.3 and below 0.6. The degree of population genetic differentiation in J. brevifolia was relatively high compared with other species, including Juniperus spp. The genetic differentiation among populations suggests that provenance should be considered when formulating augmentation or reintroduction strategies.

Keywords: Conservation genetics; Endemic plants; Genetic variability; Islands

Characterization of α/β- and γ-Gliadins in Commercial Varieties and Breeding Lines of Durum Wheat Using MALDI-TOF and A-PAGE Gels by Santiago Marín; Javier Gil-Humanes; Alberto Hernando; Francisco Barro (pp. 735-747).

In this work, gliadin composition has been analyzed in 33 accessions of durum wheat using MALDI-TOF MS and compared with A-PAGE results. The MALDI-TOF MS spectra were 29,900–42,500 Da, which corresponds to the α/β- and γ-gliadin regions in A-PAGE. The average of gliadin peaks per line was 23 for MALDI-TOF MS and only 14.8 bands for A-PAGE. MALDI-TOF MS identified 33 gliadin peaks in the durum wheat collection, 20 of which were unique peaks present in 7 lines. A-PAGE analysis identified 30 bands, of which only 4 were unique. Thus, the MALDI-TOF MS method was more sensitive than A-PAGE for identifying α/β- and γ-gliadins in the 33 durum wheat lines studied. Phylogenetic analyses performed using MALDI-TOF MS data assigned the durum wheat lines to two groups. The utility of MALDI-TOF MS to determine relationships among genotypes and for identification of durum wheat accessions is discussed.

Keywords: Gliadins; Durum wheat; Mass spectrometry; Cereal breeding

FAD2 Gene Mutations Significantly Alter Fatty Acid Profiles in Cultivated Peanuts (Arachis hypogaea) by Ming Li Wang; Noelle A. Barkley; Zhenbang Chen; Roy N. Pittman (pp. 748-759).

A panel of 55 peanut lines was analyzed for fatty acid composition with gas chromatography and also genotyped with SNP markers from the FAD2 genes by real-time PCR. Significant variation in fatty acid composition was identified, and the ratio of oleic acid to linoleic acid (O/L) ranged from 1.23 to 56.45. In terms of the FAD2 gene mutation, the assayed lines were classified into four genotypes: wild type (Ol₁Ol₁Ol₂Ol₂), single functional homozygous mutation on the A genome (ol₁ol₁Ol₂Ol₂), single functional homozygous mutation on the B genome (Ol₁Ol₁ol₂ol₂), and a double mutation on both A and B genomes (ol₁ol₁ol₂ol₂). Each genotype has a significantly different fatty acid profile. Both FAD2A and FAD2B are involved in the conversion of oleic acid to linoleic acid in peanuts. Overall, these results demonstrate the combined power of genetic analysis with biochemical analysis on peanut fatty acid research.

Keywords: Peanut FAD2 gene mutation; Real-time PCR; SNP genotyping; Gas chromatography; Fatty acid profiling

DNA Sequence Variation of the Tobacco Cutworm, Spodoptera litura (Lepidoptera: Noctuidae), Determined by Mitochondrial A+T-rich Region and Nuclear ITS2 Sequences by Xinlong Wan; Jianhong Li; Min Jee Kim; Hae Chul Park; Sung-Soo Kim; Iksoo Kim (pp. 760-787).

In an effort to gain greater insight into the nature of the population genetic structure of the pest insect Spodoptera litura (Lepidoptera: Noctuidae), tobacco cutworms were collected from six Korean and five Chinese localities, and their mitochondrial A+T-rich region and nuclear internal transcribed spacer 2 (ITS2) were cloned and sequenced. The A+T-rich region and nuclear ITS2 provided a maximum sequence divergence of 2.88 and 1.82%, respectively. Overall, a low level of genetic fixation (F _ST = 0–0.02965 in the A+T-rich region and 0–0.34491 in ITS2) and no discernible isolated population were noted among most S. litura populations. Along with these results, the absence of genetic variance between Korea and China indicates a profound interrelation of the S. litura populations in the two countries, consistent with the current notion that S. litura has sufficient flight capacity for dispersal.

Keywords: Spodoptera litura ; Mitochondrial DNA; A+T-rich region; Nuclear ITS2; Population genetics; Gene flow

Allozyme Variation and Population Genetic Structure in the Carpet Shell Clam Ruditapes decussatus Across the Siculo-Tunisian Strait by Aicha Gharbi; Rym Zitari-Chatti; Alain Van Wormhoudt; Mohamed Naceur Dhraief; Françoise Denis; Khaled Said; Noureddine Chatti (pp. 788-805).

This study reports on the polymorphism of 15 allozyme loci in Ruditapes decussatus clams collected from 11 locations along the Tunisian coasts. We concentrated our sampling effort around the Siculo-Tunisian region to verify if any population structuring exists in this region and to identify the factors that have shaped this structure. Measurements of genetic diversity were quantified both within and between populations, and the geographic variability of gene frequencies was analyzed. Our study shows that the Siculo-Tunisian Strait is an important genetic boundary between eastern and western regions, which agrees with findings for a variety of other species. We suggest that vicariance is a predominant factor shaping the current distribution of genetic diversity of R. decussatus, and the mixing of divergent gene pools from the eastern and western regions still seems to be limited by some physical and/or biological factors.

Keywords: Siculo-Tunisian Strait; Allozymes; Clines; Vicariance; Ruditapes decussatus

Genetic Diversity and Differentiation in Hedychium spicatum, a Valuable Medicinal Plant of Indian Himalaya by Arun Jugran; Indra D. Bhatt; Sandeep Rawat; Lalit Giri; Ranbeer S. Rawal; Uppeandra Dhar (pp. 806-818).

Hedychium spicatum, a perennial rhizomatous medicinal plant distributed in subtropical and temperate parts, is considered nearly endemic to the Himalayan region.In this study allozyme markers were utilized to assess genetic variations and relationships among 12 distinct populations of this species from the West Himalaya of India. A high level of genetic diversity was found among the populations. Of the 13 loci generated using eight enzymes, 12 (92%) were polymorphic. F-statistics suggested a prevalence of a high heterozygote excess among populations (F _IS = –0.51). Gene flow estimates and geographic distances between populations did not correlate significantly (r = –0.0258, P < 0.3550). The excess heterozygosity may be attributed to high pollinator mobility and inbreeding coefficient within the subpopulation, relative to the total F _IS value. High frequencies of several alleles at different loci probably reflect the breeding pattern, as the species propagates clonally as well as through seeds. We also discuss conservation implications for the target species.

Keywords: Allozyme; Conservation; Genetic diversity; Threatened; Vegetative propagation

Sections

Personal tools

Biochemical Genetics (v.49, #11-12)

Sections

Personal tools

Local resources

Biochemical Genetics (v.49, #11-12)