scholarly journals DNA Finger-Printing: Current Scenario and Future

2021 ◽  
Author(s):  
Sandeep Sitaram Kadu

Linearly arranged chemical structure in chromosome is known as DNA. It is a double helix made up of two strands of genetic material spiraled around each other. Each strand has a sequence of bases. There are four types of basis namely adenine, guanine, cytosine and thiamine which are very unique to each individual just like their actual fingerprint. The nitrogen base adenine always binds with thymine and cytosine also always binds with guanine. Thus the DNA profiling unique to each individual is collectively known as DNA fingerprinting. DNA determines individuality or uniqueness of the each human being except in uniovular twins. The chances of complete similarity are one in 30 billion to 300 billion i.e. half the population of world. The technique of DNA fingerprinting was first developed by Dr. Alec Jeffery’s from Britain in 1984. He discovered a minisatellite region close to the human myoglobin gene. He isolated this sequence and used it as a probe to investigate human DNA. He found that the minisatellite probe result was a complex band pattern for each individual. In India, initially it was done at CCMB, Hyderabad by Dr. Lalji Singh. Now there are various centers where DNA fingerprinting is carried out. In Maharashtra it is carried out at Sate Forensic Science Laboratory, Vidya Nagar, Kalina, Mumbai – 400 098 (Phone 022–26670755). Using this technique FBI formally concluded the participation of Mr. Bill Clinton in Monica Lewyninskey case. In India more than 79 cases have been solved by using this technique including important case of Dhanu and Shivarasan alleged assailant of Late Priminister Shr. Rajiv Gandhi, Tandori case, Madhumati murder case etc.

1995 ◽  
Vol 66 (3) ◽  
pp. 195-202 ◽  
Author(s):  
Anne McLaren ◽  
Paul Molland ◽  
Esther Signer

SummaryPublished reports suggest that the incidence of monozygotic twinning in women is increased after hormonally induced ovulation. Since some statistical evidence exists to indicate that monozygotic twinning may also occur in mice, we attempted to devise a mouse system in which the incidence of such twinning could be compared after spontaneous versus hormonally induced ovulation, in order to analyse the developmental basis of such an effect. We used phenotypic identity in litters segregating for ten genetic loci (not all independent) to indicate possible twin pairs. DNA fingerprinting using three human minisatellite probes was then performed blind on these pairs and on sibling controls. From a total of over 2000 mice born, 40 apparently identical pairs were identified, on which DNA finger-printing was successfully carried out on 35 pairs. All proved to be derived from different zygotes. We conclude that monozygotic twin pairs are either extremely rare in the stock of mice that we studied, or have such reduced viability that their chance of surviving to weaning is low.


1959 ◽  
Vol 5 (3) ◽  
pp. 397-404 ◽  
Author(s):  
L. D. Hamilton ◽  
R. K. Barclay ◽  
M. H. F. Wilkins ◽  
G. L. Brown ◽  
H. R. Wilson ◽  
...  

DNA's from diverse cells of different species and from diverse tissues give the same x-ray diffraction pattern. The presently observable structure of DNA appears, then, to be the same in all cells. Thus, DNA in the resting state—the stored genetic material, from sperm of Paracentrotus lividus, Arbacia lixula, and salmon and from T2 and T7 bacteriophage—gives a pattern indistinguishable from DNA from very rapidly dividing cells, e.g., human acute leukemic leukocytes, human leukemic myeloid cells, mouse sarcoma 180, and bacteria—E. coli and pneumococci—during their logarithmic growth. The same x-ray patterns are given by DNA's from more slowly dividing tissues, e.g. calf liver, calf thymus, and human normal and leukemic lymphatic tissue. DNA from chicken erythrocytes—a DNA presumably metabolically inert—gives a similar picture. DNA's from several sources with a wide range in nitrogen base ratios, prepared independently by different workers using various methods, have given final products in varying yield; these all gave the same x-ray pattern, suggesting that all DNA is in the double-helical configuration. Finally, separation of the DNA molecule into a number of fractions with a varying adenine + thymine:guanine + cytosine ratio, but a constant adenine:thymine and guanine:cytosine ratio, each giving the same x-ray pattern as the original whole molecule, suggests that DNA cannot exist in significant amounts in forms other than the double-helix. X-ray diffraction photographs of sperm heads, extracted nucleoprotamine, calf thymus nuclei and extracted nucleohistone, and of chicken erythrocyte nuclei, are not all as well defined as those given by extracted DNA, but it is clear from the general characteristics of the pattern that much of the DNA bound to protein in these nuclei has the usual helical configuration, and that the double-helical structure of DNA exists in the cell and is not an artifact.


2020 ◽  
Author(s):  
S.P. Jeevan Kumar ◽  
C Susmita ◽  
Dinesh K. Agarwal ◽  
Govind Pal ◽  
Abhishek Kumar Rai ◽  
...  

Abstract Genetic purity is conventionally performed through Grow-Out-Test (GOT) with morphological characters. Simple sequence repeat (SSR) markers are independent of G X E interaction. Herewith, 16 high yielding varieties of rice were analyzed using 55 SSR markers for DNA fingerprinting and identification of genetic impurities: 14 were found to be polypmorphic and amplified 48 alleles with an average of 3.43 alleles per each primer pair. The number of alleles amplified ranged from 2 to 6 and the size of the PCR products amplified from these 14 primer pairs ranged from 80–450 bp with polymorphic information content (PIC) from 0.14 (RM 346) to 0.99 (RM 5900). PICs at 0.5 or higher are highly informative SSR markers for genetic studies, DNA fingerprinting and scoring polymorphism rate of SSR markers pertinent to specific locus. The 14 polymorphic SSR markers can be used for DUS testing, genetic purity and DNA finger printing of rice varieties.


2018 ◽  
Vol 24 (2) ◽  
Author(s):  
VIMLESH KUMAR TIWARI

Performance of developed genotype RMT 08-2 was evaluated in central, eastern and north-eastern states of India under rain-fed condition for quantitative and qualitative traits. It gave highest seed yield over checks in zone III and V. Morphologically plants were erect, medium spreading in nature and primary branches with dichotomous habit. Plants height ranged from 107124 (cm) which matured in 82-112 days. Mature seeds were round in shape and blackish brown in colour. No significant difference between RVT-2 and checks were observed for test weight trait. An average oil yield 485 (kg/h) was recorded over 7 places which was 10% higher than both checks i.e. 14.12% and 11.24% under AICRP trials. Maximum seed yield was obtained on farmers field during 2013-14 and 2014-15 which was 1500 (kg/h) and 1215 (kg/h) that is 33.42% and 26.30% respectively over farmers own seeds. At Morena center, highest seed yield (1753 kg/h) over Bhawani (1512 kg/h) was 15.94% higher than check whereas RVT-2 gave 2245 (kg/h) against Bhawani (1975 kg/h) which was 13.67% higher. DNA finger printing indicated that primers PUT-19, PUT-96, PUT-149, PUT-169, PUT-181 and PUT-271 are useful in generating unique profile of RVT-2 containing 27 bands for its discrimination from other varieties.


2003 ◽  
Vol 36 (4) ◽  
pp. 429-453 ◽  
Author(s):  
Chantal Prévost ◽  
Masayuki Takahashi

1. Introduction 4302. Transformations of the RecA filament 4312.1 The different forms of the RecA filament 4312.2 Orientation and position of the RecA monomers in the active filament 4332.3 Transmission of structural information along the filament 4333. RecA-induced DNA deformations 4353.1 Characteristics of RecA-bound DNA 4353.2 Stretching properties of double-stranded DNA 4363.3 DNA bound to architectural proteins 4373.4 Implications for RecA-induced DNA deformations 4383.5 Axial distribution of the DNA stretching deformation 4384. Contacts between RecA and the DNA strands 4404.1 The DNA-binding sites 4404.2 Possible arrangement of loops L1 and L2 and the three bound strands of DNA 4425. Strand arrangement during pairing reorganization 4445.1 Hypotheses for DNA strand association 4445.2 Association via major or minor grooves 4465.3 Post-strand exchange geometries 4466. Conclusion 4477. Acknowledgments 4488. References 448Homologous recombination consists of exchanging DNA strands of identical or almost identical sequence. This process is important for both DNA repair and DNA segregation. In prokaryotes, it involves the formation of long helical filaments of the RecA protein on DNA. These filaments incorporate double-stranded DNA from the cell's genetic material, recognize sequence homology and promote strand exchange between the two DNA segments. DNA processing by these nucleofilaments is characterized by large amplitude deformations of the double helix, which is stretched by 50% and unwound by 40% with respect to B-DNA. In this article, information concerning the structure and interactions of the RecA, DNA and ATP molecules involved in DNA strand exchange is gathered and analyzed to present a view of their possible arrangement within the filament, their behavior during strand exchange and during ATP hydrolysis, the mechanism of RecA-promoted DNA deformation and the role of DNA deformation in the process of homologous recombination. In particular, the unusual characteristics of DNA within the RecA filament are compared to the DNA deformations locally induced by architectural proteins which bind in the DNA minor groove. The possible role and location of two flexible loops of RecA are discussed.


Author(s):  
Nadrian C. Seeman

DNA is well-known as the genetic material of living organisms. Its most prominent feature is that it contains information that enables it to replicate itself. This information is contained in the well-known Watson-Crick base pairing interactions, adenine with thymine and guanine with cytosine. The double helical structure that results from this complementarity has become a cultural icon of our era. To produce species more diverse than the DNA double helix, we use the notion of reciprocal exchange, which leads to branched molecules. The topologies of these species are readily programmed through sequence selection; in many cases, it is also possible to program their structures. Branched species can be connected to one another using the same interactions that genetic engineers use to produce their constructs, cohesion by molecules tailed in complementary single-stranded overhangs, known as ‘sticky ends.’ Such sticky-ended cohesion is used to produce N-connected objects and lattices [1]. This notion is shown in the drawing, which shows cohesion between sticky-ended branched species.


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