This presentation describes Huntington's Disease (HD), its cause & symptoms in a lucid way for naive audience with some interest in biology

1. © SUPRATIM GHATAK, PhD

2. Brain Disease

6. B
E
H
A
V
I
O
R

10. That too in discrete populations

11. 700 per 100,000
are AFFECTED

13. Pneumonia
Heart diseases
Suicide

18. Mutation in gene

19. Chromosome 4 (Human)
Exon1 Exon2 Exon3 Exon67

20. Exon1 Exon2 Exon3 Exon67
Exon1 Exon2 Exon3
CAG trinucleotide repeat region
…CAG CAG CAG CAG CAG CAG……………………………….
CAG codes

21. Exon1 Exon2 Exon3
…..CAG CAG CAG CAG CAG CAG CAG CAG………………………………….
Normally
CAG repeats up to 35

22. Exon1 Exon2 Exon3
…………CAG CAG CAG CAG ……………….CAG CAG CAG CAG CAG CAG…..
But,
in Replication
error
CAG repeats extends >36
36th

23. Exon1 Exon2 Exon3
This CAG trinucleotide expansion beyond repeat no 36
is
gene Mutation

24. QQQQQQQQQ

25. QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
Form AGGREGATES
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
QQQQQQQQQ
T O I C
to

26. Putamen
Caudate Nucleus
Globus pallidus
Nucleus accumbens
Subthalamic
nucleus
Substantia
Nigra
Striatum

27. Putamen
Caudate Nucleus
Globus pallidus
Nucleus accumbens
Subthalamic
nucleus
Substantia
Nigra

28. Basal Ganglia controls
Voluntary Limb
Movements
Cognition

29. Death of cells in basal ganglia
Due to mutant Huntingtin toxicity

30. Period after Onset of HD
Severity
5
Yrs
10
Yrs
15
Yrs
20
Yrs

32. Psychiatric
issues

33. 1872
George Huntington
describes Chorea (HD)
1983
HTT (HD gene) mapped
on chromosome 4
1993
HTT (HD gene) isolated
and mutation detected
(CAG expansion in Exon 1)
2014
still no
CURE