Seminario Biología Molecular, Tercer Semestre Medicina Universidad Pontificia Bolivariana.

1. ARTICLE REVIEW | 2023
Madeline Durango Duque
III Semester
Pontifical Bolivarian University

2. Late-onset cerebellar ataxias
(LOCAs)
Late-onset cerebellar ataxias (LOCAs) are a heterogeneous group of
neurodegenerative disorders manifesting as a progressive cerebellar
syndrome that develops after 30 years of age and it's hard to diagnose
because of limitations in molecular testing to identify sequence variations.
Introduction

3. Introduction
FGF14 is a growing factor (protein) that has a triplet of nucleotides in it´s
genome; GAA and when this triplet repeats 250 or more times in the
intronic genome of FGF14 its associated with developing the disease
(LOCA).
FGF14 GAA repeat expansion

4. Overall
Objective
The study aimed to clarify the
involvement of Deep Intronic
FGF14 GAA Repeat Expansion
in Late-Onset Cerebellar
Ataxia.

5. PCR Immunohistoc
hemistry
01 02
Methods
PCR is used to amplify DNA specific
molecules using enzymes to know if
that DNA fragments are present in
the patient's sample and in some
cases quantify it.
Technique based on using marked
antibodies to look for specific
antigens in a tissue sample and their
cell location.

6. DNA
Sequencing
Induced cells
to motor
neurons.
03 04
Methods
Is the process of determining the
nucleic acid sequence, the order
of nucleotides in DNA using
fluorochromes. This test is helpful
in identifying Polymorphisms.
Inducing pluripotent cells to
differentiate into motor neurons to
see how the disease affects this cell
type specifically.

7. Results ARTICLE REVIEW | 2023

8. Results

9. Discussion
van Swieten JC, Brusse E,
de Graaf BM, et al.
Exonic point and frameshift variants in
FGF14 have previously been shown to
cause autosomal dominant
spinocerebellar ataxia 27.
Richards S, Aziz N, Bale S, et
al.
The FGF14 (GAA)≥250 expansion is
pathogenic according to criteria of the
American College of Medical Genetics
and Genomics
Adam MP, Everman DB,
Mirzaa GM, et al.
Several lines of evidence suggest that
the FGF14 GAA repeat is highly
unstable. First, the number of FGF14
GAA repeats varies from 8 to 300 in
unaffected persons. In comparison, the
FXN repeat length ranges from 5 to 33
repeats among unaffected persons.

10. 1 2
Conclusions
Studying Genes and nucleic
acids trhu molecular biology
methods can guide doctors to
establish the origin of many
gen-related diseases
Molecular testing like PCR is
helpful in medicine to diagnose
some diseases easily and more
effective than other methods.

11. MIND MAP