Please enable JavaScript.
Coggle requires JavaScript to display documents.
MM 10 - Human Genetic Variability + Its Consequences (ii) (Pathogenic…
MM 10 - Human Genetic Variability + Its Consequences (ii)
Insertions/deletions
1/2 bases duplicated/deleted
small-scale
everyone carries approx 20 000
vast majority benign
in rare cases (e.g. in exons) case disease
micro satellites
repeated units of DNA (2-5 bases)
usually non-coding - rarely pathological
small scale
everyone carries approx 10 000
highly variable (18 is enough to distinguish you from everyone else)
Single Nucleotide Polymorphisms (SNPs)
everyone carries approx 3.5 million
vast majority benign
small scale
rare cases cause disease
e.g. if stop codon affected
1 bp changes
Pathogenic mutations
alter gene function
CNVs can increase/knock-out genes
translocations can rearrange genes
non-synonymous/missense mutations change AA
nonsense mutations introduce early stop codon + prematurely stop translation
splice-site mutations alter splicing
mutate bases between intron + exon
large scale pathology changes gene expression + protein levels
small scale pathologies
changes AA sequence
aberrant splicing (exon skipped/wrong one introduced)
premature stop
e.g. CFTR delta 508: phenylalanine deleted
protein can't leave ER to be processed
frameshift mutations
disrupts open reading frame
wrong base picked @ start of each codon
due to insertion / deletion
Cancer
somatic mutation accumulation, where 1 has hit regulatory gene
genomic instability
rapid evolution of malignant cells
driver mutations
persist genomic instability
bypass safety mechanisms (e.g. apoptosis)
allow rapid division, growth, metastasis
not a single disease (different in different tissues)
in 1 cancer different clones exist
different sensitivities to pharmacological agents
every single 1 of our cells has slightly different DNA
normal mutating