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Can someone please explain SNPs and STRs? (1 Viewer)

SadCeliac

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I understand that it has something to do with identifying individuals in a population and DNA profiling? Also that somewhere there is a <1% involved??? If someone could please clarify this whole concept that would be great

Thanks!
 
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SadCeliac

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SNP: 'typing error' where one nucleotide is replaced by another. To be termed a SNP rather than a mutation, the altered sequence must occur in at least 1% of the population
--limitation of SNPs: the altered sequence may not be passed down to offspring due to crossing over / random segregation

STR: unique sections of non-coding DNA that are repeated many times over. Therefore, number of repeats and location of STRs can be used to identify related family through sequencing and DNA profiling (e.g., using PCR to amplify STR DNA and then using gel electrophoresis to compare different profiles)
 
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SNP: 'typing error' where one nucleotide is replaced by another. To be termed a SNP rather than a mutation, the altered sequence must occur in at least 1% of the population
--limitation of SNPs: the altered sequence may not be passed down to offspring due to crossing over / random segregation

STR: unique sections of non-coding DNA that are repeated many times over. Therefore, number of repeats and location of STRs can be used to identify related family through sequencing and DNA profiling (e.g., using PCR to amplify STR DNA and then using gel electrophoresis to compare different profiles)
Yes, most of that information is right. However, be careful with STRs because they are short repeating sections of DNA that aren't necessarily sequentially unique, but unique based on how many repeats there are for each individual. You could also potentially link to haplotypes and haplogroups;
A haplotype is a specific combination of alleles (gene variants) at multiple SNP locations on a single chromosome. SNPs are variations in a single nucleotide base within the DNA sequence. When several SNPs are close to each other on the same chromosome and tend to be inherited together, they form a haplotype.

A haplogroup is a specific genetic lineage or group of individuals who share a common ancestor and exhibit a unique set of genetic markers (SNPs). Haplogroups are used in genetic and anthropological studies to trace the ancient migration patterns and evolutionary history of human populations.(links to module 5's syllabus 'human evolution' aspect)
 
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SadCeliac

done hsc yay
Joined
Sep 23, 2021
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Sydney <3
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Male
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2023
Yes, most of that information is right. However, be careful with STRs because they are short repeating sections of DNA that aren't sequentially unique, but unique based on how many repeats there are for each individual. You could also potentially link to haplotypes and haplogroups;
A haplotype is a specific combination of alleles (gene variants) at multiple SNP locations on a single chromosome. SNPs are variations in a single nucleotide base within the DNA sequence. When several SNPs are close to each other on the same chromosome and tend to be inherited together, they form a haplotype.

A haplogroup is a specific genetic lineage or group of individuals who share a common ancestor and exhibit a unique set of genetic markers (SNPs). Haplogroups are used in genetic and anthropological studies to trace the ancient migration patterns and evolutionary history of human populations.(links to module 5's syllabus 'human evolution' aspect)
Great - thank you!
 

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