Related Experiment Video
Updated: May 29, 2026

09:37
Navigating MARRVEL, a Web-Based Tool that Integrates Human Genomics and Model Organism Genetics Information
Published on: August 15, 2019
Alu pair exclusions in the human genome
George W Cook1, Miriam K Konkel, James D Major
1Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, 70803, USA. mbatzer@lsu.edu.
Mobile DNA
|September 28, 2011
Summary
Direct pairs of Alu elements are more common than inverted pairs within 350,000 base pairs in the human genome. This imbalance might contribute to genomic instability.
Area of Science:
- Genomics
- Molecular Biology
- Human Genetics
Background:
- Alu elements constitute over 10% of human DNA.
- Previous studies noted an imbalance in Alu pair orientations (direct vs. inverted) for short distances.
Purpose of the Study:
- To comprehensively analyze the ratio of inverted to direct Alu pairs across the entire human genome.
- To investigate if the previously observed imbalance extends to larger genomic distances.
Main Methods:
- Genome-wide analysis of over 800,000 full-length Alu elements.
- Statistical analysis of the inverted to direct (I:D) Alu pair ratio.
- Polymerase Chain Reaction (PCR) to verify Alu pair exclusions.
Main Results:
- A significant depression in the I:D ratio was observed for Alu pairs separated by up to 350,000 base pairs.
- Direct Alu pairs significantly outnumber inverted pairs within this 350,000 bp 'imbalance bubble'.
- Experimental verification confirmed deletions causing inverted Alu pair exclusions.
Conclusions:
- Over 50 million full-length Alu pairs exist within this imbalance region.
- The collective effect of these Alu pairs may be a previously uncharacterized source of genomic instability.
Related Concept Videos
Multi-species Conserved Sequences
Next-generation sequencing technologies have created large genomic databases of a variety of animals and plants. Ever since the human genome project was completed, scientists studied the genome of primates, mammals, and other phylogenetically distant living beings. Such large-scale studies have provided new insights into the evolutionary relationship between organisms.
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Base-pairing and DNA Repair
Erwin Chargaff’s rules on DNA equivalence paved the way for the discovery of base pairing in DNA. Chargaff’s rules state that in a double-stranded DNA molecule,
Genome-wide Association Studies-GWAS
Genome-wide association studies or GWAS are used to identify whether common SNPs are associated with certain diseases. Suppose specific SNPs are more frequently observed in individuals with a particular disease than those without the disease. In that case, those SNPs are said to be associated with the disease. Chi-square analysis is performed to check the probability of the allele likely to be associated with the disease.
GWAS does not require the identification of the target gene involved in...
GWAS does not require the identification of the target gene involved in...
Human Genetics
Human genetics provides a profound framework for understanding the interplay between genetic predispositions and human psychology. At the heart of this discipline lies the study of how genes influence physical traits, behaviors, and susceptibility to diseases. Each person carries a unique genetic code that subtly or significantly shapes their psychological and behavioral landscape.
The complex relationship between genetics and psychology is observable through common biological components such...
The complex relationship between genetics and psychology is observable through common biological components such...
Single 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,...

