GENETICS Lactase persistence in East Africa - Prevalence and genetic variability

[giire12]

Apparently for those of you who tested with 23&me. If you get AA on the Middle Eastern rs41380347, this means you are positive. Correct me if I’m wrong

You are correct,

Thanks for confirming your result again:

• rs41380347: AC

Let’s dive a bit deeper into what this means.

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rs41380347 — Lactase Persistence Variant​

• This SNP is associated with lactase persistence primarily in Middle Eastern and East African populations.
• The A allele is the derived variant and has been linked to continued lactase production into adulthood.
• The C allele is the ancestral form and does not support lactase persistence.

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Your Genotype: AC​

Genotype	Interpretation
AA	Likely lactase persistent
AC	Heterozygous — partial or likely lactase persistence
CC	Likely lactose intolerant

So in your case:

• AC suggests you may have partial or full ability to digest lactose, even if rs4988235 and rs182549 suggest otherwise.
• This is especially relevant if you have Middle Eastern, North African, or East African ancestry — the A variant is more common and functional in those groups.

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Summary of Your Three SNPs:​

SNP	Genotype	Associated Effect
rs4988235	GG	Lactose intolerant (European marker)
rs182549	CC	Lactose intolerant
rs41380347	AC	Lactase persistence (non-European variant)

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Final Interpretation:​

• Genetically, you carry non-persistence markers (GG/CC) common in Europeans.
• However, your AC at rs41380347 suggests some level of lactase persistence, particularly if your ancestry includes Middle Eastern or African backgrounds.
• In real life, this might mean:
  • You can tolerate lactose better than most people with GG/CC.
  • You may still produce lactase into adulthood, depending on how your body expresses these variants.

 

[Garaad Awal]

Do you carry the NE African one? @giire12

 

[giire12]

Do you carry the NE African one? @giire12

I am not good at it, so i asked chatgpt, it said

do I carry the North East African Lactose intolerant ?

ChatGPT said:​

Based on the genotypes you’ve already shared:

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Your Lactase-Related SNPs:​

SNP	Genotype	Interpretation
rs4988235	GG	Ancestral, lactose intolerant (European marker)
rs182549	CC	Ancestral, lactose intolerant
rs41380347	AC	Derived variant found in Northeast Africans (e.g., Somali, Beja) → associated with lactase persistence

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Interpretation:​

You do not carry the Northeast African lactase-intolerant genotype. Instead:

• You carry the Northeast African lactase-persistent variant (A allele at rs41380347).
• Your genotype AC means you have one copy of the derived allele associated with continued lactase production.
• This is the adaptive allele that evolved independently in Northeast Africans (like Somalis and Beja), separate from the European one (rs4988235-T).

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Conclusion:​

You carry the Northeast African lactase persistence allele — not the intolerant one.
This means you likely inherited the ability to digest lactose as an adult through East African ancestry, even though your European-linked markers (rs4988235/rs182549) say otherwise.
This is a great example of convergent evolution — multiple populations developed lactase persistence independently.


I think this means i have the Somali version.

Trait	You	Typical Somali
European lactase variant (rs4988235-T)	Absent (GG)	Absent (GG)
Northeast African variant (rs41380347-A)	1 copy (AC)	1 or 2 copies (AC or AA)
Overall lactase ability	Partial	Moderate to strong

 

[wonyluvr]

I love milk and cheese

 

[The alchemist]

I got these genes related to lactase persistence: rs4988236 and rs41380347.

 

[queasyian]

This is why I reduced my chop cheese sliders to once a month. Ish would make my stomach breakdance if I had it weekly, or if I have ice cream on a cheat day.

 

[The alchemist]

I did readings years back on the limited literature on this LP matter. What I found was that Somalis had around a 1/4 of their population having the checked LP variants but 75% could drink milk. It could be that we have potentially other genes that are not mapped out but what it could also mean is that we have a gut profile that can sustain milk drinking because of our descent from pastoralists since more than 8000 years back. Nilo-Saharans like the Dinka have none of the acknowledged genes, but all of them could consume milk. Here is a text piece briefly mentioning how it can be more complex:

"Equally as intriguing, several studies have also found that some pastoralist groups in South Sudan (e.g. the Dinka, Nuer and Shilluk) and the Sahel (e.g. the Moors, Tuareg and Zaghawa) have either low frequencies or an absence of the common LP polymorphisms (5,6,8,11,24,54). As one possible explanation for this phenomenon, it has been proposed that the gut microbiome might facilitate the digestion of lactose without contributing to the development of gastrointestinal symptoms (particularly, if H2-producing bacteria are absent in the colon)"

What's interesting is that, farming groups like Nubians and Europeans, when they lack those genes, it is a complete consitent cutoff, those individuals dont consume milk. So the percentage of Nubians with the LP polymorphisms matches the milk drinking population frequency. The same with Europeans. The same cannot be said about historical pastoralists.