Related Experiment Video
Updated: Aug 3, 2026
06:50
Dissection, Histological Processing, and Gene Expression Analysis of Murine Supraclavicular Brown Adipose Tissue
Published on: March 29, 2024
Chromosomal polymorphism of mandarin vole, Microtus mandarinus (Rodentia)
1Department of Biology, School of Life Sciences, Shandong University, Jinan, P.R. China. jxwang@sdu.edu.cn
Hereditas
|July 2, 2003
Summary
Chromosomal analysis of the mandarin vole revealed significant polymorphism, including variations in chromosome number and structure. These findings shed light on the karyotype evolution in this rodent species.
Area of Science:
- Cytogenetics
- Mammalian Genetics
- Evolutionary Biology
Background:
- The mandarin vole (Microtus mandarinus) is a rodent species found in China.
- Understanding chromosomal diversity is crucial for evolutionary studies and conservation efforts.
Purpose of the Study:
- To analyze the mitotic and meiotic chromosomes of the mandarin vole.
- To identify and characterize chromosomal polymorphism and karyotype evolution in the species.
Main Methods:
- Conventional staining
- G-banding
- C-banding
- Silver-staining techniques
- Karyotype analysis
Main Results:
- Detected chromosomal polymorphism with diploid numbers ranging from 2n = 48-50.
- Identified variable morphology in the 1st chromosome pair, a telocentric pair, and X chromosomes.
- Revealed four distinct karyotypes within the population, indicating pericentric inversion, Robertsonian fusion, and translocation events.
Conclusions:
- The karyotype evolution of Microtus mandarinus involves structural rearrangements like inversions and fusions.
- The observed X chromosome polymorphism suggests pericentric inversion and autosome translocation as contributing factors.
Related Concept Videos
02:32Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
02:04Polytene Chromosomes
Polytene chromosomes are giant interphase chromosomes with several DNA strands placed side by side. They were discovered in the year 1881 by Balbiani in salivary glands, intestine, muscles, malpighian tubules, and hypoderm of larvae Chironomus plumosus. Hence, these are also called "Salivary gland chromosomes." These are found in insects of the order Diptera and Collembola; in certain organs of mammals; and synergids, antipodes of flowering plants. Polytene chromosomes are also regularly...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
01:43Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
02:26Comparing Copy Number Variations and SNPs
Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
01:05Single Nucleotide Polymorphisms-SNPs
A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...