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1.
Summary Chromosome aberrations permit the assignment to and the exclusion of genes on certain chromosomes or definite segments. Only exclusion methods are discussed. All relevant data are compiled in a table from which it can be determined, which genetic systems are excluded from certain autosomal segments.
Direktor: Prof. Dr. Dr. H. Baitsch
Supported by the Deutsche Forschungsgemeinschaft. 相似文献
Zusammenfassung Angeborene Chromosomenaberrationen ermöglichen die Zuordnung und den Ausschluß von Genen auf dem betroffenen Segment. Nur die für Lokalisierungsausschlüsse verwendbaren Methoden werden diskutiert. Aus einer Zusammenstellung der bisherigen Befunde wird ermittelt, welche genetischen Systeme von einer Lokalisierung auf bestimmten Autosomen(segmenten) des Menschen ausgeschlossen werden können.
Direktor: Prof. Dr. Dr. H. Baitsch
Supported by the Deutsche Forschungsgemeinschaft. 相似文献
2.
Ferdane Kutlar Jose M. Gonzalez-Redondo Abdullah Kutlar Aytemiz Gurgey Çigdem Altay Georgi D. Efremov Klara Kleman Titus H. J. Huisman 《Human genetics》1989,82(2):179-186
Summary Details are given of a study of blood samples from 24 patients with Hb H disease from different Mediterranean countries and from the Far East. Four different types of -thal-1 (--) were observed, namely-() ( 20.5-kb deletion);--MED-I ( 17.5-kb deletion);--MED-II (>26.5-kb deletion); and--SEA ( 18-kb deletion, in Orientals only). The -thal-2 was mainly of the deletion type (16 with the 3.7-kb deletion; 1 with the 4.2-kb deletion), while 4 of the 7 patients with a nondeletional type had the five-nucleotide deletion at the donor splice site of the first intron of the 2 gene. All patients had a mild-to-moderate hemolytic anemia; no significant differences in hematology were observed between the groups. Hb A2 was decreased to about one-third of the normal level. The Hb H formation varied considerably and its quantitation was not always satisfactory. Patients with Hb H disease due to any -thal-1 combined with a nondeletional -thal-2 had the highest Hb H levels and a more marked anemia. The chain production was small and absent in patients with the MED-II type of -thal-1 because this deletion included the and genes. The highest chain levels were present in the four patients with the SEA type of -thal-1. The chain production was increased, particularly in patients with a mutation of C T at position-158 to the G globin gene. This chain was primarily present as Hb Bart's (or 4) and only about 15% was recovered as Hb F or 22. The evaluation of the rate of chains produced in these patients was greatly facilitated by data from one patient who had Hb H disease and a heterozygosity for the A-+. The low levels of Hb A2 and of Hb F (relative to Hb Bart's) can be explained by a decreased affinity of chains for and chains as compared with chains in conditions of severe chain deficiency. 相似文献
3.
Factors affecting the initiation of mini-rhizomes from Trillium erectum and T. grandiflorum tissues in vitro 总被引:1,自引:0,他引:1
Leaf and stem explants of Trillium grandiflorum and T. erectum produced mini-rhizomes (MRs) in vitro which gave rise to shoots and roots. The apical portion of the stem and the basal portion of the leaves were the most effective explants from these tissues, while stem tissue was more responsive than leaf tissue. The best response with both species was observed on half-strength MS basal medium supplemented with cytokinin and auxin. T. erectum was more responsive than T. grandiflorum overall, and in some cases produced MRs in the absence of growth regulators. Culture at 21°C appeared to stimulate growth from T. grandiflorum tissues, compared with controls at 27°C, whereas the outgrowth of shoots from MRs was inhibited in both species at 21°C. In vitro production of MRs could provide a more rapid, alternative propagation method for these species than traditional methods. 相似文献
4.
Batdorj Enkhjin AlOgayil Najla Zhuang Qinwei Kim-wee Galvez Jose Hector Bauermeister Klara Nagata Kei Kimura Tohru Ward Monika A. Taketo Teruko Bourque Guillaume Naumova Anna K. 《Mammalian genome》2023,34(1):44-55
Mammalian Genome - Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on... 相似文献
5.
6.
Development of immunohistochemical characteristics of intrafusal fibres in normal and de-efferented rat muscle spindles 总被引:1,自引:0,他引:1
Summary Intrafusal muscle fibres in adult muscle spindles differ in their myosin composition. After selective motor denervation intrafusal muscle fibres develop mature ultrastructural characteristics. In order to evaluate the role of fusimotor innervation on the maturation of the myosin composition of intrafusal muscle fibres we have examined with immunohistochemical techniques i) the postnatal development of muscle spindles in new-born rats and in 7–21 day old rats; ii) muscle spindles in the EDL of 21-day-old rats de-efferented at birth. For the characterization of myosins in intrafusal fibres we used three myosin antisera: antipectoral myosin, antiheart myosin and antiheart myosin adsorbed with muscle powder from the soleus muscle of guinea pig. We show in this study that during development intrafusal fibres change immunoreactivity and that in the absence of motor innervation bag fibres do not fully develop the myosin characteristics of control spindles. We conclude that the maturation of bag1 and bag2 fibres apparently requires next to the inductive influence of sensory axon terminals the presence and activity of fusimotor axons. 相似文献
7.
Karyotypes of five American bald eagles (Haliaeetus leucocephalus and H. alacanus) are compared. All had 2n=66 chromosomes which fell into 3 size groups: A, 20 pairs of biarmed chromosomes; B, 9 pairs of acrocentric chromosomes and C, 4 pairs of microchromosomes. C-banding was done in two eagles and a heterochromatic W chromosome was identified in a presumptive female. The ZZ and ZW chromosomes could be identified in the karyotypes. 相似文献
8.
Klara M. Wanelik Joanne S. Griffin Megan L. Head Fiona C. Ingleby Zenobia Lewis 《Ecology and evolution》2020,10(14):6870-6880
The academic disciplines of Science, Technology, Engineering and Mathematics (STEM) have long suffered from a lack of diversity. While in recent years there has been some progress in addressing the underrepresentation of women in STEM subjects, other characteristics that have the potential to impact on equality of opportunity have received less attention. In this study, we surveyed 188 early career scientists (ECRs), defined as within 10 years of completing their PhD, in the fields of ecology, evolutionary biology, behaviour, and related disciplines. We examined associations between ethnicity, age, sexual orientation, sex, socioeconomic background, and disability, with measures of career progression, namely publication record, number of applications made before obtaining a postdoc, type of contract, and number of grant applications made. We also queried respondents on perceived barriers to progression and potential ways of overcoming them. Our key finding was that socioeconomic background and ethnicity were associated with measures of career progression. While there was no difference in the number of reported first‐authored papers on PhD completion, ethnic minority respondents reported fewer other‐authored papers. In addition, ECRs from a lower socioeconomic background were more likely to report being in teaching and research positions, rather than research‐only positions, the latter being perceived as more prestigious by some institutions. We discuss our findings in the context of possible inequality of opportunity. We hope that this study will stimulate wider discussion and help to inform strategies to address the underrepresentation of minority groups in the fields of ecology and evolution, and STEM subjects more widely. 相似文献
9.
Continuous-time Markov processes are often used to model the complex natural phenomenon of sequence evolution. To make the process of sequence evolution tractable, simplifying assumptions are often made about the sequence properties and the underlying process. The validity of one such assumption, time-homogeneity, has never been explored. Violations of this assumption can be found by identifying non-embeddability. A process is non-embeddable if it can not be embedded in a continuous time-homogeneous Markov process. In this study, non-embeddability was demonstrated to exist when modelling sequence evolution with Markov models. Evidence of non-embeddability was found primarily at the third codon position, possibly resulting from changes in mutation rate over time. Outgroup edges and those with a deeper time depth were found to have an increased probability of the underlying process being non-embeddable. Overall, low levels of non-embeddability were detected when examining individual edges of triads across a diverse set of alignments. Subsequent phylogenetic reconstruction analyses demonstrated that non-embeddability could impact on the correct prediction of phylogenies, but at extremely low levels. Despite the existence of non-embeddability, there is minimal evidence of violations of the local time homogeneity assumption and consequently the impact is likely to be minor. 相似文献