Question

How does admixture provide information about the past? please in simple terms

Answer 1

During the first phases of molecular evolution, mitochondrial DNA sequences (maternal ) and Y chromosome DNA sequences(paternal) were utilized as hereditary markers to trace ancestry. The primary reason for this was that both, mitochondrial DNA sequences as well as Y chromosome DNA sequences have been gender certain, which made tracking simpler.

Nevertheless, within the present situation, monitoring the track of haplogroups along with haplotypes is possible. This's due to the accessibility of genome sequencing methods and information about countless Single Nucleotide Polymorphisms (SNPs) inside the genome.

When two  people belonging to various population have kids, the kids have new arrangement of alleles. This unique pattern of gene variants belongs to a hereditary admixture.
The primary reason for occurrence of hereditary admixture is migration. It's also essential to be aware that the current human population are genetically admixed. In case, in case crossing over usually takes place, compared to the haplotype design gets modified from one generation to another. By monitoring the haplotype design changes, it's possible to monitor the admixture.

Additionally, the occurrence of admixture may be realized whether the speed of crossing over of particular gene is known. This specific gene is the gene, that participates within interchange of genetic content. In this particular situation, the rough generation time will be years.

The altering info of haplotypes will be estimated with the assistance of specialised computer software tools. By coordinating the above information together with the admixture, gene variants which existed before million years could be reconstructed. Due to developments in genetics, exact information is contained by the admixtures. Hence, the risks of error are less.

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