Context:
An article in The Hindu| What our ancestors’ genomes can tell us about modern health
Ancient DNA (aDNA):
- DNA that is isolated from ancient specimens
- It is extracted from the tissue or bone of a museum specimen or other preserved remains
- Studies uses cutting-edge genomic techniques of Genetic Engineering
Cutting-edge genomic techniques:
- Technology used for genome study under Genetic Engineering
- CRISPR/Cas9 – Simultaneously edit two genetic sites on the same chromosome
- For bacterial gene expression analysis –
- RNA sequencing (RNA-Seq)
- Single-cell RNA sequencing (scRNA-Seq)
- Mass spectrometry-based proteomics
- Study rare cancer-related mutations –
- Digital PCR (dPCR)
- Next-generation sequencing (NGS)
Chromosomal abnormalities:
- Disorders that can occur during cell division or in the early stages of fetal development
- Results in chromosome number changes – Extra copies or deletions of entire chromosomes – resulting in different clinical syndromes
- Down’s syndrome – Caused by an extra chromosome 21
- Klinefelter’s syndrome – Due to an extra X chromosome
- Turner syndrome – Loss of one of the two X chromosomes in women
Chromosomal karyotyping:
- A method to visualise the complete set of chromosomes in a cell
- Best techniques to diagnose abnormalities
- It requires live cells, which in turn requires scientists to adopt laborious methods to culture and stain them.
Paleogenomics:
- Also known as genome-wide ancient DNA analysis
- A scientific field that involves analyzing and reconstructing genomic information from extinct species
Read more about: CRISPR/Cas9, Genome Sequencing
Source: The Hindu
Previous Year Question
Consider the following statements:
1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.
2. Common cold is sometime caused by an adenovirus whereas AIDS is caused by a retrovirus.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2021 Prelims]
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (b)
Explanation:
Statement 1 is not correct:
Adenoviruses have double-stranded DNA genomes while Retroviruses have single-stranded DNA genomes.
