Gene Editing in a Human Embryo | Burning Issues

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A Chinese researcher recently made a claim that he had altered the genes of a human embryo that eventually resulted in the birth of twin girls.

The researcher worked with seven volunteered couples, wherein each couple had one partner who was HIV-positive.
The aim was to ensure that HIV is not transmitted to the child.
He used the Crispr Cas9 technology, which works like a genetic cut-and-paste tool, that allows researchers to permanently modify genes in living cells and organisms.
Under the technology, he edited the genomes of 16 embryos to disable a gene, CCR5, which allows HIV to infect cells.
He then used the in-vitro fertilisation (IVF) technique to implant edited embryos, that lead to the birth of genetically edited babies.
The changes so made are inheritable and passed on to descendants.

CRISPR (short for Clustered Regularly Interspaced Short Palindromic Repeats) technology is a relatively new, and the most efficient tool for gene “editing” developed in the last one decade.

The technology replicates a natural defence mechanism in bacteria to fight virus attacks, using a special protein called Cas9.
The specific location of the genetic codes that need to be changed is identified on the DNA strand.
Using the Cas9 protein, which acts like a pair of scissors, the specified location is cut off from the strand.
A DNA strand, when broken, has a natural tendency to repair itself.
Scientists intervene during this auto-repair process, supplying the desired sequence of genetic codes that binds itself with the broken DNA strand.

The most promising use of the CRISPR technology is in treatment of diseases.
In the case of the new-born Chinese babies, the genes were “edited” to ensure that they do not get infected with HIV.
Leading scientists in the field have for long been calling for a “global pause”

Complications to create a “designer” baby
Disabling of the CCR5 gene is known to lead to higher risks such as heightened susceptibilit y to flu.
Targeting Since the changes are inheritable.
Population composition – Genetic editing in humans with customised traits could empower eugenicists and racists, thereby encouraging selective breeding of the human population by eliminating undesirable traits.

Gene editing is banned in most countries.
In the UK, where gene editing of embryos is permitted only after strict regulatory approval.
Hence, many people from the scientific community have asked for a moratorium on editing human embryos.
The scientific, commercial and ethical implications of this technique have to be researched further before getting it implemented on a large scale.