Page 66 - Cell biology PDG 2024

enzyme that reduces ribonucleotides to generate deoxyribonucleotides.
The effectiveness of the immune system depends upon lymphocyte
proliferation and hence dNTP synthesis. Without functional
ribonucleotide reductase, lymphocyte proliferation is inhibited and the
immune system is compromised.
Ashanti lacked a healthy immune system and was vulnerable to many
infections and children suffering from this disease rarely survive to
adulthood.
In 14/9/1990, Ashanti DeSilva became the first of only two participants in
the world's first approved gene therapy.
In Ashanti's gene therapy procedure, her own white blood cells were
taken, then they were genetically modified and infused back into her
bloodstream. This strengthened Ashanti's immune system as she no
longer has recurrent colds and has been allowed to attend school.
The genetically-treated white blood cells only survived for a few months
and must then be replaced so additional ADA was injected which might
have contributed to the only transient success of the gene therapy and
Ashanti grew up normally into adulthood

By the end of this chapter the student should know:
1) Design and carryout practical work
2) Correlate experimental techniques and results with potential
clinical applications
3) Develop skills of independent learning through searching to get
information

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