In the context of recent advances of human reproductive technology, “Pronuclear Transfer” is used for

[UPSC Civil Services Exam – 2020 Prelims]

(a) fertilization of egg in vitro by the donor sperm

(b) genetic modification of sperm producing cells

(c) development of stem cells into functional embryos

(d) prevention of mitochondrial diseases in offspring

Answer: (d)        

Explanation:

Pronuclear Transfer    

• It involves the transfer of pronuclei from one zygote to another.
• This technique first requires fertilisation of healthy donated egg/eggs provided by the mitochondrial donor with the intending male parent sperm.
• The intending mother’s affected oocytes are fertilised with the intending father’s sperm.
• Thereafter, both sets of fertilised oocytes are allowed to develop to the early zygote stage where the pronuclei are visible.
• The pronuclei of zygotes formed from donated oocytes are removed within a karyoplast using micromanipulation equipment, and then it is discarded.
• The resulting zygotes contain nuclear DNA from each of the intending parents and a donor’s mtDNA.