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interpreting Interpreting matches with low cM values and high SNPs (or vise-versavice versa)?

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TJK
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On GEDmatch's autosomal one-to-one report, a match contains a column for cM and a column for SNPs values, for each of the matching chromosomes. Normally you look for high cM values as an indicator of genetic distance (and to some degree, generational distance). But I also understand that it's important to take into account the number of SNPs in relation to the cM value (the greater the SNPs, the better it is).

But, in my research, I've discovered high cM values with very low SNPs (for example, a common value that I find is: 14cM / 128SNP). On the other hand, I have very low cM values with very high SNPs (3.2cM / 4968SNPs).

I've not found these contrasting amounts useful for establishing valid matches so far (and often delete them from my database). But I'm wondering if I should take these "extreme" segment matches more seriously -- do they have any value? How should I interpret them?

On GEDmatch's autosomal one-to-one report, a match contains a column for cM and a column for SNPs values, for each of the matching chromosomes. Normally you look for high cM values as an indicator of generational distance. But I also understand that it's important to take into account the number of SNPs in relation to the cM value (the greater the SNPs, the better it is).

But, in my research, I've discovered high cM values with very low SNPs (for example, a common value that I find is: 14cM / 128SNP). On the other hand, I have very low cM values with very high SNPs (3.2cM / 4968SNPs).

I've not found these contrasting amounts useful for establishing valid matches so far (and often delete them from my database). But I'm wondering if I should take these "extreme" segment matches more seriously -- do they have any value? How should I interpret them?

On GEDmatch's autosomal one-to-one report, a match contains a column for cM and a column for SNPs values, for each of the matching chromosomes. Normally you look for high cM values as an indicator of genetic distance (and to some degree, generational distance). But I also understand that it's important to take into account the number of SNPs in relation to the cM value (the greater the SNPs, the better it is).

But, in my research, I've discovered high cM values with very low SNPs (for example, a common value that I find is: 14cM / 128SNP). On the other hand, I have very low cM values with very high SNPs (3.2cM / 4968SNPs).

I've not found these contrasting amounts useful for establishing valid matches so far (and often delete them from my database). But I'm wondering if I should take these "extreme" segment matches more seriously -- do they have any value? How should I interpret them?

Source Link
TJK
TJK
  • 133
  • 6

interpreting matches with low cM values and high SNPs (or vise-versa)

On GEDmatch's autosomal one-to-one report, a match contains a column for cM and a column for SNPs values, for each of the matching chromosomes. Normally you look for high cM values as an indicator of generational distance. But I also understand that it's important to take into account the number of SNPs in relation to the cM value (the greater the SNPs, the better it is).

But, in my research, I've discovered high cM values with very low SNPs (for example, a common value that I find is: 14cM / 128SNP). On the other hand, I have very low cM values with very high SNPs (3.2cM / 4968SNPs).

I've not found these contrasting amounts useful for establishing valid matches so far (and often delete them from my database). But I'm wondering if I should take these "extreme" segment matches more seriously -- do they have any value? How should I interpret them?