Single-variant targeted testing
Do you need to confirm one specific mutation? We sequence exactly that variant by bidirectional Sanger and deliver a report with interpretation validated by the responsible physician. €132 per variant · 7 days.
One variant, one answer
When the question is not “which variants are there?” but “is this specific variant present?”, a full panel is overkill. Here you pay for what is actually analysed.
Confirming a candidate
An exome, a genome or a panel has identified a candidate variant and you need confirmation with an orthogonal method before reporting or continuing the investigation.
Segregation testing
Check whether the variant segregates with the disease in the family: one targeted assay per relative, each with its own report.
Follow-up of a known case
Verification of a variant already described in the patient, in a previous report or in the family prognostic work-up.
An order without a full panel
You only care about one specific position of the DNA: this test analyses that position and nothing else, with a fixed turnaround and price.
Anesthetic susceptibility: the MT-ND4 m.11232T>C variant
Targeted study of a single mitochondrial DNA variant (MT-ND4 m.11232T>C), associated in the literature with severe neurological complications after general anesthesia with halogenated agents in people of Venezuelan maternal lineage. Anesthesiology and pharmacogenetics societies recommend considering this analysis during preoperative assessment for that group, with informed consent and genetic counseling. This is not population screening.
Who it is for
Direct Venezuelan maternal lineage (mother or maternal grandmother born in Venezuela; includes mother of unknown origin or from egg donation), scheduled for general anesthesia or sedation with halogenated agents.
Sample and turnaround
1 mL peripheral blood with EDTA or saliva/buccal swab (laboratory protocol); no fasting required. 7 days (2 in urgent mode).
What it reports
Presence or absence of the variant, with its mutational load (heteroplasmy, %) when detected, in a report validated by a physician.
- Uncertain significance. The causality of the variant is not established (ClinVar, 07-10-2026).
- A negative result only rules out this variant; it does not guarantee absence of risk from other causes.
- A positive result does not contraindicate surgery when it is indicated, provided a safe anesthetic alternative can be ensured.
- Maternal inheritance. Mitochondrial DNA is passed down the maternal line: a positive result is relevant to relatives on the maternal line (targeted family study possible).
Sources: SEFF press release (29-04-2026) · SEDAR statement (31-03-2026) · Rev Esp Anestesiol Reanim 2026 (PMID 42685863, PMID 42685860).
Get the technical note (PDF)
Leave your professional email to download the one-page note with the cited sources (SEFF, SEDAR, PubMed) and the study limitations. We will only send communications if you explicitly authorise it in the form.
From variant to report in 4 steps
1 · Send us the variant
Gene and HGVS notation, at DNA and/or protein level (e.g. DES NM_001927.4:c.1345A>G). If you do not have the transcript reference, we locate it and confirm it with you before starting.
2 · Sample and consent
Peripheral blood in a K2 EDTA tube (other samples on request). Kit, labels and collection coordinated with your centre, informed consent included.
3 · Bidirectional Sanger sequencing
Amplification of the region containing the variant and reading of both strands, with internal quality control and technical review before interpretation.
4 · Validated report
Report within 7 days of sample receipt: result, interpretation according to inheritance and genotype, variant context, references and limitations, signed by the responsible physician.
A report you can defend
Tailored interpretation
The text is composed according to the inheritance and genotype detected (dominant, recessive, X-linked, mitochondrial) and complemented with the specific context of the variant.
Cited evidence
ClinVar classification, ClinGen gene–disease validity, OMIM entries and primary articles referenced inside the report itself, with the date of consultation.
Declared limitations
The report states what the assay does not cover: only the requested variant, no detection of CNVs or large rearrangements, and an explanation of allele dropout.
Fixed, no surprises
Targeted test
Bidirectional Sanger + report
- Bidirectional sequencing of the region
- Report with interpretation and references
- Validation by the responsible physician
- 7 days from sample receipt
What this test does NOT do
Saying it clearly avoids wrong expectations:
- It does not analyse other variants. Only the requested position; it is not a panel or an exome and it does not rule out variants in other genes.
- It does not detect CNVs or large rearrangements. Duplications, deletions and structural variants are not assessed.
- It does not prove that “both alleles are reference”. A variant in a primer-binding site or the loss of one allele (allele dropout) can hide that allele; the report states this.
- It is not a prenatal or presymptomatic diagnostic test unless there is a clinical indication and previous genetic counselling.
Ask for your targeted test
Tell us the gene and the variant (HGVS) and we confirm feasibility, quote and kit dispatch. You can also contact us directly.
Frequently asked questions
Which variants can be tested?
Any single nucleotide variant or small indel described in any gene, in HGVS notation (c. or g., and p. if you know it). If you only have the nucleotide change, we locate the transcript reference and confirm it with you before starting.
How much does it cost and how long does it take?
€132 per variant and 7 days from sample receipt at the laboratory. The quote is confirmed before the kit is sent.
Which sample is required?
Peripheral blood in a K2 EDTA tube. For other materials (extracted DNA, saliva, tissue) please check first: viability depends on the quality and quantity of the material.
Does it replace a panel or an exome?
No. This test answers one concrete question (“is this variant present?”) and does not rule out variants in other genes or structural variants. For a broad diagnostic work-up see our targeted panels or the clinical exome.
Can it be used to test relatives?
Yes: it is the standard assay for segregation studies. Each relative requires their own sample and their own report.
What exactly do I receive?
A PDF report with the result, the interpretation according to inheritance and genotype, the variant context with cited sources, the limitations of the assay and validation by the responsible physician. You can see a sample report.
Who should consider the MT-ND4 test?
People of direct Venezuelan maternal lineage (mother or maternal grandmother born in Venezuela, including mother of unknown origin or from egg donation) who are to receive general anesthesia or sedation with halogenated agents. Screening in the general population is not recommended.
Does a negative result guarantee a safe anesthesia?
No. It only rules out this variant in the sample; the clinical significance of the variant is still under study (uncertain significance classification).
What if it is positive?
It does not cancel an indicated surgery: it informs your anesthesiologist to plan alternatives (according to current scientific-society recommendations). A relative on the maternal line can repeat the test on a targeted basis.
Do you have a specific variant in mind?
Gene + HGVS and you are done: quote confirmed, kit sent, report in 7 days.