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My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this is division Basidiomycota. The fungi here is division Ascomycota and these are very distinct from Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa). The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date and sequences are unique to any known species. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven artifactual). In the latter PCR mosaic artefact I'm referring to (which I wouldn't cite), was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the extant ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling bias, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it definitely looks genuine but it is not the species you think it is, in fact not even close.

My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this is division Basidiomycota. The fungi here is division Ascomycota and these are very distinct from Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa). The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date and sequences are unique to any known species. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven artifactual). In the latter PCR mosaic artefact I'm referring to (which I wouldn't cite), was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the extant ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling bias, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it definitely looks genuine but it is not the species you think it is, in fact not even close.

My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this division, Basidiomycota. The fungi here is division Ascomycota and these are very distinct from division Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa). The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date and sequences are unique to any known species. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven artifactual). In the latter PCR mosaic artefact I'm referring to (which I wouldn't cite), was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the extant ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling bias, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it definitely looks genuine but it is not the species you think it is, in fact not even close.

My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this is division Basidiomycota. The fungi here is division Ascomycota and these are very distinct from Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa). The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date and sequences are unique to any known species. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven artifactual). In the latter PCR mosaic artefact I'm referring to (which I wouldn't cite), was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the extant ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling bias, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it definitely looks genuine but it is not the species you think it is, in fact not even close.

My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this division, Basidiomycota. The fungi here is division Ascomycota and these are very distinct from division Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa) from the fungal spore (I presume. The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven). In the latter PCR mosaic artefact (which I wouldn't cite), this was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling error, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it looks genuine but it is not what you think it is.

My conclusion from the tree is the fungi appears to be genuine and not an extant contaminant (which is very easily done). It is not Fomitopsis betulina because this division, Basidiomycota. The fungi here is division Ascomycota and these are very distinct from division Basidiomycota.

There have been many examples of contamination in ancient DNA work, but this doesn't appear to be one of them. The rationale is given below.

The first fragment was not interesting and described 100% identity to ascomycetes. The tree above is a simple distance tree from the second fragment of 18S which shows it is an outgroup to the ascomycetes (green terminal taxa). The ancient fungi contains 3 (I think) unique nucleotide residues that have not been sequenced in any extant ascomycetes to date and sequences are unique to any known species. The location of the 3 unique nucleotides is tightly clustered within the locus with 100% identities either side. This is significant because it demonstrates it is not a PCR mosaic artefact (yep its been done in ancient DNA work and subsequently proven artifactual). In the latter PCR mosaic artefact I'm referring to (which I wouldn't cite), was a fungi/bacterial mosaic from memory.

Given the homology of 18S in the extant ascomycetes I would say this appears to be a new genus, however you would need to be sure this was not sequencing error and this is very old DNA, which is subject to degradation even when frozen. The implication of the tree is quite unusual, it implies widespread extinction of this group of fungi in recent history (5000 years is slight in evolutionary terms) BUT it could be a sampling bias, i.e. no one has sequenced those fungi and NCBI is not representative.

I assume that you have performed phenotypic/morphological analysis on the spore to believe it is Basidiomycota.

The fragment in yellow is the query and the sequence next to it was the sequence already deposited on Genbank of this ancient isolate. You would need to look up the biology and ecology of ascomycete to understand its significance, but it is in a lineage of its own, so maybe difficult to interpret by comparison to extant species. You could concatenate the two alignments based on each fragment, but the problem with 18S is that is a hard to model and you'd need to perform secondary RNA structure modelling to assess whether these mutations would be viable.

In conclusion, it definitely looks genuine but it is not the species you think it is, in fact not even close.