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FISH (fluorescent in situ hybridization) is a molecular cytogenetic technique established in the early 1980s that allows for the detection of DNA copy number changes (gains and losses) mapping to genomic regions of interest (Langer-Safer et al. Proc Natl Acad Sci USA 79:4381–4385, 1982). This technology has been extensively applied to research-based investigations and is routinely used in prenatal diagnosis and oncology. Here we describe a modification of the standard FISH protocol adapted for the detection of low-frequency mosaic aneuploidy in interphase cells. This approach represents a straightforward method for the measurement of aneuploidy levels in mammalian cells. This system combines four probes mapping to two different chromosomes. The choice of probes is essential for the successful performance of this approach. It greatly reduces the enumeration of false-positive signals that are challenging in the enumeration of ploidy changes (particularly if these are complex and/or involve a significant increase of chromosome number). [ABSTRACT FROM AUTHOR]

Brassicaceae (crucifers or the mustard family) is a large plant family comprising over 330 genera and about 3,700 species, including several important crop plants (e.g. Brassica species), ornamentals as well as model organisms in the plant sciences (e.g. Arabidopsis thaliana). In recent years, the wealth of Arabidopsis and Brassica genomic resources along with newly established tools and techniques fostered the unprecedented progress in phylogenetics and genomics of crucifers. Multigene phylogenetic analyses paved the way for a new infrafamiliar classification based on phylogenetically circumscribed genera and tribes. A new generation of comparative genetic, cytogenetic, and genomic studies as well as whole-genome sequencing projects unveil general principles of karyotype and genome evolution in Brassicaceae. [ABSTRACT FROM AUTHOR]

The article offers information on the family or class of wheatgrass. These include Barley grass, Kamut and Rye. It mentions that the first member of its family is one of the top green cereal grasses which rivals it in nutritional content. The second is an ancient desert wheat that contains 28 chromosomes while the third reduces cholesterol, prevents cancer and treat digestive disorder. It also points out that these classes of wheatgrass are loaded with essential nutrients for good health.

To better understand the regulatory role of nucleosomes, it is important to pinpoint their positions in the DNA sequence. In this paper, we present a pattern recognition algorithm to predict the locations of nucleosomes. Based on a number of features of the nucleosomal architecture, a computational framework based on the probabilistic relaxation labeling technique is developed to infer the nucleosome centers along the DNA sequence of simian virus 40 (SV40). Using this method, we can detect about 70% of the SV40 nucleosome locations with high probability (> 0.9). The proposed algorithm improves the flexibility and efficiency in nucleosome positioning, and makes it easy to analyze nucleosome structure without expensive wet-lab biological experiments. Our results show that the framework is practicable and has potential in its applications. In fact, only the significant periodicity of DNA dinucleotides is employed in our current algorithm as a nucleosomal feature. We believe that more pattern recognition techniques can be developed to improve the prediction accuracy of nucleosome positions by employing more sequence features. [ABSTRACT FROM AUTHOR]

This work presents a differential evolution algorithm for solving a single-item resource-constrained aggregate production planning (APP) problem. Due to its NP-hardness, we have developed a Differential Evolution (DE) for solving the above model with a real representation of chromosomes, adapting DE with the integer nature of the problem. Experiments were carried out to compare results from the differential evolution algorithm and local optimum solutions obtained by optimization software. [ABSTRACT FROM AUTHOR]

The evolution of the horse was certainly a most tortuous process. None of your seven day nonsense! Seven days' labour wouldn't evolve one primitive earthworm. There are interesting parallels between the structuring of multicellular organisms and societies. We see the same elements of aggregation, communication, commitment and differentiation, and although some regret the decline of the protean ideal, specialization was a minor penalty to pay for the development of modern society. After all, more people have flown in aeroplanes than ever held a pilot's licence, and more have enjoyed the benefits of surgery than ever wielded a scalpel. And how many of us would be meat eaters if we had to do our own butchering? There are even similarities in the way societies and multicellular organisms subordinate the individual to the point of dispensability. A nation survives the death of any citizen, however prominent, and a mature organism hardly seems to notice replacement of its individual cells. Moreover, it now appears that the collective structure has a vested interest in the mortality of its members; the multicellular organism follows a policy of programmed death, and a steady turnover increases the chance of a favourable mutation. This too might have its social counterpart; what happens to individual members after they have procreated is of minor importance, and old worn-out citizens are replaced by fresh young individuals. [ABSTRACT FROM AUTHOR]

Twist ye, twine ye! even so Mingle shades of joy and woe, Hope and fear, and peace and strife, In the thread of human life. All molecules in a living organism serve a purpose, and we cannot say that a particular type is more important than any other. Nevertheless, it would be difficult to identify substances that play more varied and central roles than do the biopolymers. They contribute to the mechanical structure, and in the animal kingdom they provide the means of motion. They facilitate transport of smaller chemical units and mediate the chemical interaction between molecules, the biopolymers that serve this catalytic function being the proteins known as enzymes. There are biopolymers that form the immunological system and others that are involved in the mechanism of tissue differentiation. With so many functions to be fulfilled, we should expect to find many different types of these ubiquitous molecules, and this is certainly the case. It is believed, for example, that there are several hundred distinct enzymes within each cell of a higher organism such as a mammal. Even the task of perpetuating and translating the genetic message is entrusted to biopolymers. The body of a typical mammal is mostly water – about 65% by weight in fact – but of the solid components no group is better represented than the proteins; they make up about 15% of the total weight. [ABSTRACT FROM AUTHOR]

A million million spermatozoa, All of them alive: Out of their cataclysm but one poor Noah Dare hope to survive. And among that billion minus one Might there have chanced to be Shakespeare, another Newton, a new Donne, But the One was Me. Although biopolymers are more sophisticated than their simpler cousins, such as polythene and rubber, this alone does not give them an obvious reason for existing. Nucleic-acid codes for proteins, some of which contribute to the formation of further nucleic acid, but if these products were free to float away through the surrounding water, no advantage would be gained by the original molecule. The essential extra factor was discovered over 300 years ago. In 1663, using one of the earliest microscopes, Robert Hooke observed that cork has a structure reminiscent of a honeycomb, with pores separated by diaphragms so as to produce a collection of little boxes, which he called cells. Their universality was not appreciated until 1824, when Henri Dutrochet concluded that entire animals and plants are aggregates of cells, arranged according to some definite plan. He also suggested that growth is caused by an increase in either cell size or cell number, or both. The idea of the cell was further elevated in 1838, when Matthias Schleiden proposed that it is the basic structural unit in all organisms. [ABSTRACT FROM AUTHOR]

Chapter 6 of the book "Journey Across the Life Span" is presented. It discusses heredity and environment and its influence on the health of the developing baby. It focuses on the prenatal period, which starts from conception to childbirth, and describes the physical development of the newborn. It also discusses the importance of nutrition, sleep and rest, and play to the growth and development of a child.

The article presents a lesson plan for students which teaches concepts about the differences in every individual for satisfying the theory of natural selection by scientist Charles Darwin and further discusses how traits are passed to the offsprings. As mentioned, material used in the activity includes pumpkins, paper cups and scale. According to Darwin, all living things are made of cells in which genes are stored in chromosomes, a part of a cell.

Chapter 9 of the book "Garden Genetics: Student Edition" is presented. It discusses the quantitative trait loci studies to examine tomato fruit size. Techniques used by plant breeders to find the multiple genes involved in quantitative traits are discussed. An activity is presented wherein students can use published data to create a genetic chromosome map of regions associated with red color in tomato.

In this chapter we describe how the molecular methods were then applied to resolving the riddle of the origin of races. Only within the past three years have three separate molecular dating methods--autosomal DNA, mitochondrial DNA (which is inherited only through the maternal line), and Y-chromosome DNA (which is inherited only along the paternal line)--converged to produce a consistent picture that now proves the monogenist viewpoint correct. Our species first arose in Africa only about 50,000 years ago. None of the living races can be traced back to before this date. [ABSTRACT FROM AUTHOR]

Telomerase, which is selectively expressed in germline or cancer cells, is a ribonucleoprotein polymerase that contains an integral RNA with a short template element that can compensate telomeric loss by synthesizing TTAGGG repeats at chromosome ends. Telomeres appear to be critical for the integrity of chromosomes, stabilizing them from exonucleolytic degradation, preventing chromosome-to-chromosome fusions, and determining the maximum replicative capacity of cells. During the past decade, the roles of telomere length and telomerase activity have been investigated extensively in a variety of benign and malignant tumors of human origin, and stronger telomerase activity has been observed in more advanced tumors. Generally, the acquisition of telomerase activity in cancer cells is rather universal, which suggests that telomerase inhibition as a novel and potentially selective target for therapeutic intervention. Although a telomerase-specific inhibitor has not been found yet, the possible effect of anticancer agents on telomerase inhibition or the alteration of telomere length has been proposed. Recent development of TRAP assay not only increased the sensitivity but also allowed fast and efficient detection of telomerase activity. Technical aspects of this assay using self-established internal standard and nonradioisotopic detection method are addressed in this report. In addition, an overview of how to determine the telomere length is described. [ABSTRACT FROM AUTHOR]

This chapter introduces the methods necessary for the readers to achieve their scientific goals and provide references for more advanced studies of particular issues. A discussion of genetics is also included. The appendix contains a brief glossary of some of the genetic and statistical terms used in this chapter. [ABSTRACT FROM PUBLISHER]

A definition of the term "tumor suppressor genes" is presented. It refers to those genes whose products negatively regulate cell growth or cell behavior. The characteristics of a tumor suppressor gene are described. A primary evidence of tumor suppressors is genetic. A diagram is presented that illustrates chromosomal mechanisms for tumor suppressor gene inactivation.

An encyclopedia entry for replication licensing system is presented. It is defined as a system that ensures that no sections of chromosomal DNA are replicated more than once in a single cell cycle. Information on how the system works is presented, including the replication of eukaryotic chromosomes and precise chromosome duplication. Furthermore, the two components of the replication licensing system are described.

An encyclopedia entry for the term "interphase cytogenetics" is presented. It refers to the analysis of chromosomes in non-dividing nuclei which does not need metaphase chromosomes. Interphase cytogenetics is useful because detection of chromosomal aberrations is important in managing diseases. It also provides a unique visualization of aberrations in cancer tissues.

A definition of the term "EWS-FLI1 fusion transcripts" is presented. It refers to the result of a balanced reciprocal chromosomal translocation between chromosomes 11 and 22, which fuses the EWS gene in chromosome 22 to the FLI1 gene in chromosome 11. This fusion transcript is sighted in the Ewing family of tumors and is considered a tumor-specific molecular rearrangement.

A definition of the term "DPC4" is presented. It refers to Deleted in Pancreatic Carcinoma Locus 4 and belongs to the class of tumor suppressor genes. DPC4 was identified within chromosome band 18q21.1 which is often deleted in pancreatic carcinoma. It is also known as Smad4 or MADH4. It is a component of the transcription complex that mediates cell surface signals to the nucleus which are initiated by transforming growth factor Β-related growth and differentiation factors.

A definition of the term "deleted in malignant tumors 1 (DBMT1)" is presented. It refers to a gene located at human chromosome 10q25.3-q26.1 that shows frequent deletions on both of its chromosomal copies in malignant brain tumors. DMBT1 codes for an extracellular glycoprotein belong to the superfamily of scavenger receptor cysteine-rich proteins.

A definition of the term "BCR-ABL1" is presented. It refers to a hybrid gene that is formed when the genomic DNA of the BCR gene on chromosome 22 and of the ABL1 gene on chromosome 9 breaks and recombines. A hybrid messenger RNA is produced when the hybrid gene is transcribed. Mutation of the gene causes some types of leukemia.

A definition of the term "BCL6 translocations in B-cell tumors" is presented. It refers to chromosomal translocations involving the 3q27 chromosome band. A chromosomal translocation fuses a BCL6 gene on 3q27 to either one of the three immunoglobulin genes (IG) and another non-IG partner. The 3q27 translocation may sometimes coexist with other IG translocations related to B-cell tumors.

A definition of the term "aneuploidy" is presented. It refers to the condition of having either less than or more than the normal diploid set of chromosomes in a cell. This may lead to a major imbalance in the genetic makeup of the affected cells. Germline inheritance of aneuploid condition often leads to developmental defects.

A definition of the term "acute promyelocytic leukemia" (APL) is presented. It refers to a distinct subtype of acute myeloid leukemia characterized by the expansion of leukemic cells blocked at the promyelocytic stage of the myelopoiesis. APL is distinct from other subtypes of leukemia. It is associated with reciprocal chromosomal translocations involving the retinoic acid receptor u gene on chromosome 17.