Karyotypic races of the common shrew (Sorex araneus L.) from northern Poland

Summary Karyotypic races of the common shrew which differed with respect to the combinations of chromosome arms in certain 2-armed autosomes were distinguished in Poland. Two eastern races with the arm combinationik, and one western race with the arm combinationhi in the third pair of autosomes were established. In the contact area of these chromosomal forms, the fourth karyotypic race with the arm combinationhk was found.I wish to express my gratitude to my wife, A.M. Wójcik, M. Sc., for her help in catching the animals and making chromosome preparations. I must also offer my thanks to Dr J. Zima for giving me access to his as yet unpublished data, and to Prof. Z. Pucek and Dr S. Fedyk for reading the first draft of this paper.     

Chromosomal and morphological diversity in 2 populations of Asian mountain vole, Alticola lemminus Miller (Rodentia, Cricetidae).

Voles from Yakutia and Chukotka were found to differ in the morphology of 3 pairs of autosomes and sex chromosomes, as well as in M3-structure and skull dimensions. This makes their conspecificity doubtful. A variation in short arm lengths of the X- and Y-chromosomes has been discovered.     

Chromosomal and morphological diversity in 2 populations of Asian mountain vole,Alticola lemminus Miller (Rodentia,Cricetidae)

Summary Voles from Yakutia and Chukotka were found to differ in the morphology of 3 pairs of autosomes and sex chromosomes, as well as in M³-structure and skull dimensions. This makes their conspecificity doubtful. A variation in short arm lengths of the X- and Y-chromosomes has been discovered.     

Zur Polymorphie eines Chromosoms innerhalb von Populationen des LaufkäfersCarabus auronitens Fabr

Summary C. auronitens has 26 autosomes (2n), from which one pair — calledA-chromosomes — is relatively long.A-chromosomes consist of an euchromatic and a heterochromatic arm. In 63% of the individuals, theA-chromosomes are intraindividually anisomorph with regard to the length of their heterochromatic arm. According to its length, this arm shows 0–3 secondary constrictions. Hence there are at least 4 different forms of theA-chromosome.     

Robertsonian translocation,pericentric inversion and heterochromatin block in the evolution of the Tailless Fruit Bat

Summary The karyotype ofMegaerops ecaudatus from Peninsular Malaysia consists of 24 chromosomes as compared to 2n=26 for specimens from Thailand. The difference in diploid number is the result of Robertsonian translocation. The Peninsular Malaysian specimens also exhibit pericentric inversion in the smallest pair of autosomes, and the presence of a totally heterochromatic short arm in the second longest metacentric pair. There is 1 pair of Ag-NOR, located on the secondary constriction of the longest metacentric autosome.This work is supported by a University of Malaya research grant.     

Heterochromatization in opossum,Didelphys virginiana

Conclusion Somatic heterochromatization of the opossum,D. virginiana, was studied from prophase and tritiated thymidine-labeled metaphase chromosome preparations. In both sexes of this mammal, a number of prophase autosomes and the sex chromosomes were observed displaying deeply stained condensed areas. These chromosomal areas were interpreted as evidence for heterochromatization. The extent of heterochromatization in the opossum was found much greater in certain autosomes than either theX orY chromosome alone. This assertion that some opossum autosomes possess more heterochromatin than the sex chromosomes was supported by data collected on the terminal labeling patterns of the chromosomes. Metaphase autoradiographs prepared from cultured leucocytes of the animals unequivocally suggested that certain opossum autosomes completed replication later than the sex chromosomes. If one assumes that there is heterochromatin in the autosomes, as the evidence suggests, then it merely becomes a question as to what block of heterochromatin replicates last — a phenomenon that is probably size dependent.

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Résumé L'héterochromatisation somatique de l'opossum (Didelphys virginiana) a été étudiée sur des préparations de chromosomes aux stades de la prophase et de la métaphase, la thymidine ayant été utilisée comme marqueur. Dans les 2 sexes de ce mammifère de nombreux autosomes et les chromosomes sexuels montrent, à la prophase, des plages denses fortement colorées. Ces plages chromosomiales ont été interprétées comme un signe évident d'héterochromatisation. L'héterochromatisation est beaucoup plus accentuée dans certains autosomes que dans les chromosomesX ouY. Les autoradiographies de stades métaphasiques dans des préparations effectuées de leucocytes en cultures suggèrent d'une façon non équivoque que certains autosomes de l'opossum achèvent leur réplication plus tardivement que les chromosomes sexuels. Si l'on assume que l'héterochromatine est présente dans les autosomes, comme le démontrent nos observations, il semble évident que l'héterochromatine autosomale a un rôle significatif dans le développement.

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Supported in part by Baylor University College of Medicine General Research Grant (No. P-13) and grants from the James Picker Foundation and the Texas Heart Association. The auther wishes to thank Dr.W. Hill for his help at the vivarium and MissMarion Gay and MissShirley Powell for technical assistance. The editorial assistance of MissMarilyn Morningstar is also appreciated.     

Un cas nouveau de polymorphisme chromosomique intraspécifique chez un Mammifère (Leggada minutoides Smith. Rodentia-Muridae)

Summary The African mouse,Leggada minutoides Smith, shows a chromosomal polymorphism: a first male (Coast of Ivory) had 32 chromosomes; theX is a big metacentric, theY a big submetacentric and the autosomes are acrocentric, with the single exception of the biggest pair which associates two submetacentric elements. By a second male (Congo), 33 chromosomes are found, amongst them only one big submetacentric autosome. This statement and the odd diploid number shows clearly that we have to deal with an heterozygot, two acrocentric elements representing respectively one arm of the submetacentric autosome. Now, we may be sure that this male belongs to a population built of individuals having 32, 33 and 34 chromosomes. The origin of such a population must have arisen in a primitive population where 34 was the diploid number, through a centric fusion.Such cases pose the question of the balanced chromosomial polymorphism and of the adaptative value of each formula⁶.     

Factors which influence normal values for serum lactic dehydrogenase in mice

Résumé Nous avons étudié, chez la souris normale, l'effet du sexe, de l'âge et de la constitution génétique sur l'activité du sérum LDH. Le seul résultat positif constaté est un rapport entre l'âge et la race. Nous avons établi la portée normale de l'activité du LDH dans cinq races de souris. Son augmentation n'est pas provoquée par une infection due au virus polyome, mais peut être mise en relation avec la constitution génétique de l'animal.     

Cytogenetic observations inCeratitis capitata

Summary The 2n=10+XX/XY complement ofC. capitata includes3 pairs of metacentric and 2 pairs of submetacentric autosomes; theX andY chromosomes are acrocentrics. The sex chromosomes do not pair somatically during mitotic prophase, and, using the C-banding technique, band more extensively than the autosomes. Male meiosis may be achiasmate; there is no leptotene, zygotene or diplotene.Material kindly supplied by Dr.D. A. Lindquist, I.A.E.A./FAO Vienna, Austria.     

A new chromosome race ofSorex araneus L. from Northern Poland

Summary G-band patterns were studied in the chromosomes of two Polish populations of the common shrew. Two chromosome races were established in Poland, differing by various combinations of chromosome arms.     

Hybridization between Robertsonian karyotypic races of the common shrewSorex araneus

Summary British common shrews of the Aberdeen, Oxford and Hermitage Robertsonian karyotypic races were hybridized successfully in captivity. Hybrids, both simple Robertsonian heterozygotes and double Robertsonian heterozygotes with monobrachial homology, have been identified in an area of contact between the Oxford and Hermitage races. The relative fertility of these two types of hybrid is considered.I thank Dr. C. E. Ford F. R. S., Prof. F. W. Robertson and Dr A. E. Douglas for reading earlier drafts of this paper, Prof. F. W. Robertson, Dr J. R. K. Savage and Dr J. R. Clarke for laboratory facilities, Mrs J. E. Evans for technical assistance and S.E.R.C. for financial support.     

Pharmacokinetics of pindolol in Africans.

The pharmacokinetics of pindolol were determined in 12 hypertensive African subjects after a single oral dose of the drug. The estimated pharmacokinetic parameters do not differ significantly in Africans from the values which have been obtained in other races.     

Serum creatine kinase in marathon runners

Serum creatine phosphokinase (CK) and CK-MB activity were determined in 21 trained runners participating in a marathon race (42.2 km). Enzyme activities immediately after the race increased two to three times compared with activities before the race. The greatest increases were found in the slowest runners, suggesting greater skeletal muscular trauma in the least trained or fit. As these are likely to include the older athletes who are also more likely to suffer acute myocardial injury during strenuous exercise, our findings assume special import in the interpretation of increased CK and CK-MB serum activities of older athletes.     

Centromeric heterochromatin in the karyotype of the male Greater Kudu (Tragelaphus strepsiceros)

Summary The chromosomes of a male Kudu (Tragelaphus strepsiceros) have been studied by C-banding and H³ thymidine labelling. It is suggested that heterochromatin may have accumulated on the 14th pair of autosomes before its translocation to the Y-chromosome.     

Sex determination in mammals — Before and after the evolution of SRY

Therian mammals (marsupials and placentals) have an XX female: XY male sex chromosome system, which is homologous to autosomes in other vertebrates. The testis-determining gene, SRY, is conserved on the Y throughout therians, but is absent in other vertebrates, suggesting that the mammal system evolved about 310 million years ago (MYA). However, recent work on the basal monotreme mammals has completely changed our conception of how and when this change occurred. Platypus and echidna lack SRY, and the therian X and Y are represented by autosomes, implying that SRY evolved in therians after their divergence from monotremes only 166 MYA. Clues to the ancestral mechanism usurped by SRY in therians are provided by the monotremes, whose sex chromosomes are homologous to the ZW of birds. This suggests that the therian X and Y, and the SRY gene, evolved from an ancient bird-like sex chromosome system which predates the divergence of mammals and reptiles 310 MYA. Received 4 March 2008; received after revision 22 April 2008; accepted 3 June 2008     

Serum creatine kinase in marathon runners

Summary Serum creatine phosphokinase (CK) and CK-MB activity were determined in 21 trained runners participating in a marathon race (42.2 km). Enzyme activities immediately after the race increased two to three times compared with activities before the race. The greatest increases were found in the slowest runners, suggesting greater skeletal muscular trauma in the least trained or fit. As these are likely to include the older athletes who are also more likely to suffer acute myocardial injury during strenuous exercise, our findings assume special import in the interpretation of increased CK and CK-MB serum activities of older athletes.Acknowledgments. The authors wish to thank the members and president of the Columbia Track Club for their cooperation.     

Chromosome banding patterns and the nucleolar organizer region of the eastern mole (Scalopus aquaticus)

Summary The C and G chromosome banding patterns and the AgAS positive sites (NOR regions) of cultured lung cells of the Eastern mole (Scalopus aquaticus) are presented. A distinctive secondary constriction is found on a pair of autosomes instead of on the X-chromosome as previously believed. The presence of a heterochromatic heteromorphism is noted and a large amount of constitutive heterochromatin is present in the karyotype.     

A mitochondrial DNA polymorphism in honeybees (Apis mellifera L.)

Summary Mitochondrial DNA (mtDNA), isolated from worker honeybee larvae, was digested by each of seven 6-base restriction enzymes. Only one enzyme (BglII) showed a mtDNA difference between the three tested races (Apis mellifera carcia, A. m. ligustica, A.m. caucasica). BothA.m. carnica andA.m. ligustica showed the same pattern, differing fromA.m. caucasica. The degree of fragment pattern similarity revealed that there is only a small level of mtDNA variation between the three races tested. This is in line with previous investigations of enzyme polymorphisms.     

Pharmacokinetics of pindolol in Africans

Summary The pharmacokinetics of pindolol were determined in 12 hypertensive African subjects after a single oral dose of the drug. The estimated pharmacokinetic parameters do not differ significantly in Africans from the values which have been obtained in other races.Acknowledgments. We would like to thank the management of Sandoz (Nigeria) Limited for assistance in these studies.     

Pheromone behavioral responses in unusual male European corn borer hybrid progeny not correlated to electrophysiological phenotypes of their pheromone-specific antennal neurons

In genetic studies on the sex pheromone communication system of two races of European corn borer, which use opposite pheromone blends of the E and Z compounds, it was found that antennal olfactory cell response amplitudes to the two compounds were controlled by an autosomal factor, whereas behavioral responses to the blends were controlled by a sex-linked locus. Because of the difference in genetic controls, it was postulated that some unusual males would be produced in F₂ crosses between these two races. These unusual males would have antennal olfactory cells that respond as the Z-race males, but would respond behaviorally to the E blend. The present studies combined behavioral studies in a flight tunnel and single cell electrophysiological studies to show that these unusual males do indeed exist. These findings show that the spike amplitude of peripheral olfactory cells is not important in regulating species- or race-specific pheromone responses, as compared to some central nervous system factor assesses the spike frequencies from different pheromone-component-specific cells on the antenna. This factor seems to be essential in governing the pheromone-blend specific behavioral responses of male moths.