الفهرس 
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Abstract
God Making! Earth is life home in the universe, Creating the face of the earth millions of organisms, different in the types and forms and sizes, the mismatch, animals and microorganisms plants that do not see with the naked eye, and each of those items is made up of millions of species, for example, the plants alone is made up of millions species and the same applies to animals and microorganisms, and all this diversity of organisms need system to regulate them in groups this system called ” taxonomy”.
The importance of taxonomy in that it facilitates the study of living organisms, as well as the classification of organisms associated with lots of other sciences as a science ecology, agriculture and science of medicine and pharmacology.
Organisms are the basis of life and are classified by scientists in terms of type, shape and adapt to the environment and what to eat and benefit from that knowledge of species how to care for them and methods of treatment and what to eat it.
We have selected eight different species of rats and mice and gerbil which are common presence in the Egyptian environment all of which belong to the family Muridae which include 3 subfamilies which are:
Subfamily: Acomyinae
Which include Genus Acomys.
Subfamily: Murinae
Which include Genus Rattus and Genus Mus.
Subfamily: Gerbillinae
Which include Genus Gerbillus.
The species under study are:
1. Acomys cahirinus (Abu Shouk) (spiny mouse) It is characterized by offer hair brown on the back with faint color, tail length as body length, this species is belong to Genus: Acomys.
2. Rattus rattus (black rat) is characterized by brown colour, and the advantage of tail longer than the length of the head and body together provide with scales, big ears and it belongs to Genus: Rattus
3. Rattus norvegicus, a rat with a strong structure and a tail shorter than the length of the head and body together. His body has fur coats and dark brown color on the back and white belly abdomen. And it belongs to the Genus: Rattus
4. Albino Rattus norvegicus has a large size and white color reared in the laboratories.
5. Mus musculus is represented the smallest mouse. With faint brown back and white colour abdomen. Eyes small and has a short foot. It belongs to Genus: Mus
6. Albino Mus musculus has white features and its small size and reared in the laboratory.
7. Gerbillus gerbillus adapted on wildlife while inner ear accommodates enabling it to hear the faint voices as well as their ability to stand under hard conditions as the lack of food. It belongs to Genus: Gerbillus.
8. Gerbillus pyramidum has a long tail cover with much hair it belongs to Genus: Gerbillus.
Similarities and differences and the degree of kinship between these species was through genetic studies through the study of numbers and structures of chromosomes for each species, biochemical studies through protein and molecular through the level of DNA located in mitochondria (mitochondrial DNA) and comparison of genes in this study, one of genes existing on m-DNA is cytochrome oxidase subunit 1 (COI), one of the important genes which carry the synthesis of proteins task blade in the final stage of the electron transport chain which is one of the important stages in the process of production power units within the ATP.
Chromosomal studies:
Metaphase chromosomal spreads were prepared from bone marrow for each animal. The metaphase chromosomes were investigated by conventional Giemsa staining to carry out the karyotype study as well as Giemsa-trypsin to study the G-banding patterns.
from the karyotype, the chromosomal count (2n) for female and male Acomys cahirinus was 36 pair of chromosomes while fundamental number (FN) was 68 arms. The relative chromosome lengths for the sex chromosomes (X,Y) were 9.3% and 1.8% respectively.
Total number of chromosomes of Mus musculus is the same number of Albino Mus musculus and equal to 40 pair of acrocentric chromosomes and fundamental number equal to 40 arms. The G-banding show obvious white and dark bands in both strains which enable us to construct ideogram. The sequence of banding pattern of chromosomes pair numbers 4,8,10,13 and 15 are similar in both strains, this may indicate a common evolutionary ancestor. The rest of chromosomes of the 2 strains display fairly different pictures. Also, the difference was included in the banding pattern of sex chromosomes. The relative chromosome length for the sex chromosomes X for black and white Mus musculus were 4.4% and 7.8% respectively while The relative chromosome length for the sex chromosomes Y chromosome were 3% and 3.2 for black and white Mus musculus respectively.
The total number of chromosomes of Rattus rattus is equal 38 pair while number of chromosomal arms equal to 60 arms Total number of chromosomes of Rattus norvegicus & Albino Rattus norvegicus equals 42 pair while the fundamental number equal to 64 arms. The relative chromosome length for the X chromosomes for three different strains (rattus) were 6.2%, 5.9%, 4.6% for Rattus rattus, Rattus norvegicus, Albino Rattus norvegicus respectively. The G-banding show obvious white and dark bands in both strains which enable us to construct ideogram. The sequence of banding patterns of matching chromosome no. 10.14 and 16 is similar in both strains of brown and white Rattus norvegicus. The rest chromosome pairs are difference from each other.
Total number of chromosomes of Gerbillus gerbillus 43 pair and fundamental number is 80 arms has complex system of sex chromosomes where it has a chromosome X (Large Subacrocentric chromosomes), Y1 (medium submetacentric chromosome), Y2 (small Subacrocentric chromosome). The total number of chromosomes of the Gerbillus pyramidum are 38 pair and no.of chromosomal arms is 76 arms. The relative chromosome lengths for the sex chromosomes were 12.3%, 3.7% and 1.8% for X, Y1 and Y2 chromosomes of Gerbillus gerbillus respectively and 6.8% and 4.5% for X,Y1 and Y2 chromosomes of Gerbillus pyramidum respectively. G-banding pattern analysis showed clear successive dark and white bands, which characterized each chromosome pair in both species and facilitated accurate arrangement of chromosomes in pairs. G-banding patterns revealed some similarities along sex chromosomes of both species; this may indicate a common evolutionary ancestor. It was suggested that, the X-chromosomes of both species are compound chromosomes and composed of X-autosome translocation, which increased the relative length.
Biochemical studies:
The amount of protein obtained showed one package of proteins on native gel at RF .2 which reflecting high degree of similarity called homomorphism between samples.
In which appear band at RF 0.4 to only species Gerbillus gerbillus, Gerbillus pyramidum and Acomys cahirinus which means high link between Genus gerbillus and Acomys than to athours under study. This is another band at Rf 0.7 at species Gerbillus gerbillus, Gerbillus pyramidum, Mus musculus, Rattus rattus, Rattus norvegicus, Albino Rattus norvegicus.
This results show high link between genus gerbillus and genus Acomys in which Acomys cahirinus near to Gerbillus than Rattus and Mus.
Molecular studies:
The family Muridae is one of the most ubiquitous invasive families all over the world and in Egypt is particularly common and wide spread. Here we investigated the degree of similarity and divergences between 8 species related to the family Muridae of common occurrence in Egypt through molecular analysis of mitochondrial DNA (COI gene) comparing between Acomys cahirinus, Mus musculus, Albino Mus musculus, Rattus rattus, Rattus norvegicus, Albino Rattus norvegicus, Gerbillus gerbillus and Gerbillus pyramidum in Egypt. Our result showing astrong link between Acomys cahirinus and Genus gerbillus than to genus Mus and Rattus with high bootstrap support.
As a result of molecular studies have shown that Acomys cahirinus different for all of them, but the nearest race Gerbillus from the rest of the species under study where it’s closer to Gerbillus sp. by degree of similarity equal to 82% .
This work provides evidence that G-banding, the protein bands and molecular study are useful tools to discriminate between very closely related taxa and various types in same family. This work is recommended the use of G-banding technique in comparative cytogenetic studies.