DNA & Deep Ancestry

DNA & Deep Ancestry

What a 23andMe v5 genotyping chip (614,453 markers, human genome build 37) says about my two oldest family lines — the strictly paternal Y‑chromosome line and the strictly maternal mitochondrial line — plus a handful of well‑studied trait and health‑linked variants.

Derived from the raw genotype file, not from any 23andMe report. Haplogroup calls were made against the ISOGG Y‑tree and PhyloTree mtDNA build 17. Trait / health notes describe published statistical associations for common variants — they are not a diagnosis, a clinical test, or medical advice. A 30× whole‑genome sequence is the fuller source for anything health‑related.

My two deepest lines

Everyone has exactly one unbroken paternal Y line (father→father→…) and one unbroken maternal mitochondrial line (mother→mother→…). Each carries a "haplogroup" — a branch of the human family tree defined by a set of mutations that never recombine, so they trace tens of thousands of years cleanly. Curiosity: both of mine land in haplogroup I — in two completely independent systems. Coincidence, but a tidy one.
Paternal line · Y‑DNA
I1
I‑M253  ·  branch of haplogroup I, itself one of the oldest Y lineages in Europe

Haplogroup I split off roughly 27,000–30,000 years ago and belonged to Europe's Ice‑Age hunter‑gatherers. The I1 sub‑branch then passed through a severe bottleneck and exploded from a single man who lived about 4,600 years ago in southern Scandinavia / Jutland — the Nordic Bronze Age. From there it spread with Germanic‑speaking peoples, and later Anglo‑Saxons and Norse. Today it peaks in Scandinavia (~35–40% of men in Sweden and Norway) and stays high across Denmark, the Netherlands and northern Germany.

In my tree: the Y line is the Demuth surname, documented back to Anton Demuth (b. 1769) of Kappelrodeck, a village in Baden, south‑west Germany, then four more generations there before Joseph DeMuth emigrated and the line settled in St. Louis.
M253 derivedM170 (I) derived M89 (F) derivedR1b / J / E / G / I2 all ancestral hint of I‑S2078 sub‑branch
Maternal line · mtDNA
I1b
haplogroup I → I1 → I1b  ·  an uncommon European maternal lineage (~2% of Europeans)

Mitochondrial haplogroup I arose about 30,000 years ago in the Near East / West Asia (it sits under macro‑haplogroup N, next to the N1a line). It entered Europe before the last glacial maximum and turns up in ancient DNA from Mesolithic and Neolithic Europe. It never became common — today it's scattered thinly across Europe, a little higher in the north‑west and around the Near East and Caucasus. I1b is a small sub‑branch marked by the mutation T6227C.

In my tree: the mitochondrial line runs Jeff → Christine Frame → Florence Graceffa → Maria Antoinett Prestia (b. 1888, Italy) — a Sicilian maternal line. A rare northern‑flavoured European lineage arriving via southern Italy fits Sicily's deep layering of Near‑Eastern, Greek and North‑African ancestry.
T10034C, T10238C, G1719AC16223T, G16129A, G16391A G6734A, G9966A (I1)T6227C (I1b)

How the two lines got here

A schematic of the deep migrations behind each haplogroup — broad population movements over tens of thousands of years, ending at the documented arrival points in my tree. These are illustrative routes for the lineage, not literal ancestor tracks.
Paternal — Y‑DNA I1 Maternal — mtDNA I1b

Traits & ancestry markers

Common variants with well‑established, everyday effects. Genotypes are on the plus strand of build 37, as 23andMe reports them.
Gene / markerSNPMy genotypeWhat it means
APOE (ε type)rs429358 T / rs7412 CTT / CC ε3/ε3 — the most common APOE genotype (~60% of people). No ε4 and no ε2.
LCT (lactase persistence)rs4988235AG One copy of the "keep digesting milk as an adult" allele — lactose tolerant (it's dominant). Typical of Northern European ancestry.
ACTN3 (R577X)rs1815739TT 577XX — no functional α‑actinin‑3 in fast‑twitch muscle (~18% of people). The "leans endurance, not pure sprint / power" genotype.
CYP1A2 (*1F)rs762551AA Fast caffeine metaboliser — clears caffeine quickly.
ABCC11 (earwax / body odour)rs17822931CT Wet earwax phenotype, carrying one copy of the "dry earwax / low odour" allele.
MC1R (R151C)rs1805007CT Carrier of a red‑hair / fair‑skin variant — associated with fairer skin, freckling and higher sun sensitivity; a red‑hair carrier for kids.
HERC2 / OCA2 (eye colour)rs12913832GG Predicts blue / light eyes (~90% accurate in Europeans).
SLC24A5 (skin pigment)rs1426654AA The light‑skin allele, near‑universal in Europeans.
ALDH2 (alcohol flush)rs671GG No "Asian flush" allele.
ACKR1 / Duffyrs2814778TT Duffy‑positive (not the Duffy‑null variant common in African ancestry).

Health‑associated markers

Read this carefully. These are statistical associations from population studies of common variants — each usually shifts risk by a small amount and is only one of many factors. This is not a clinical test and not medical advice. A chip like this also misses most rare, high‑impact variants; the 30× whole‑genome sequence is the place to look for those.
MarkerSNPGenotypeNote
APOE ε3/ε3rs429358 / rs7412TT / CC favourable No ε4 (the late‑onset Alzheimer's / lipid risk allele) and no ε2.
Factor V Leidenrs6025CC not a carrier The most common inherited clotting disorder — absent here.
HFE (haemochromatosis)rs1800562 / rs1799945GG / CC not a carrier Neither the C282Y nor the H63D iron‑overload mutation.
FTO (BMI / obesity)rs9939609TT favourable No copies of the common higher‑BMI allele.
TCF7L2 (type 2 diabetes)rs7903146TT worth watching Homozygous for the single strongest common T2D variant (~1.4× per T allele; ~10% of Europeans are TT). Diet / weight / activity still dominate — a reason to keep an eye on fasting glucose and HbA1c.
9p21 (coronary artery disease)rs1333049CG one copy One copy of the common CAD‑risk allele (present in roughly half of Europeans); small effect.
VKORC1 (warfarin dose)rs9923231TT pharmacogenomic Associated with higher warfarin sensitivity — a lower starting dose. Only relevant if ever prescribed warfarin (and dosing also depends on CYP2C9, not on this chip).
OPRM1 (opioid response)rs1799971AG pharmacogenomic One copy of the A118G variant — in some studies linked to needing somewhat higher opioid doses for pain relief.
FOXO3 (longevity)rs2802292GT one copy One copy of the allele over‑represented in long‑lived cohorts. Weak but replicated.
GC (vitamin D level)rs2282679GT minor One copy of the allele associated with slightly lower circulating 25(OH)D — a reason not to be surprised by a low‑ish vitamin D on labs.

Sample quality

Basic checks on the raw file.
Markers genotyped
614,453
23andMe v5 chip, build 37
Call rate
~98.2%
no‑calls at ~11k SNPs
Autosomal heterozygosity
17.1%
of 593,613 biallelic autosomal SNPs — normal, no runs‑of‑homozygosity flag
Sex check
Male
single X (14,712 haploid calls) + Y present
mtDNA variants vs rCRS
21
used for the maternal haplogroup call
Y‑SNPs on chip
3,337
2,909 matched to ISOGG markers

Source: 23andMe raw genotype export (v5 chip, ~614k SNPs, GRCh37 / build 37, plus‑strand calls), Sept 2026. Not derived from any 23andMe report.

Method: Y haplogroup called by scoring derived vs ancestral state at ISOGG Y‑tree markers (2016 build); mtDNA haplogroup by comparing the chip's MT calls to the revised Cambridge Reference Sequence and matching defining mutations against PhyloTree mtDNA build 17. Trait and health notes cite published associations for common variants.

Not medical advice. Genotyping arrays are for research, education and curiosity — not diagnosis. Single‑variant interpretation carries real caveats; a clinician and a proper clinical test are the right path for anything that matters. See also the family tree and the gene explorer (30× whole‑genome).