(300 days)
The AncestryDNA Saliva Collection Kit is intended for use in the noninvasive collection of saliva samples for in vitro diagnostic testing of human DNA. Saliva may be collected by spitting directly into the AncestryDNA Saliva Collection Kit by a lay user. Saliva samples collected using the AncestryDNA Saliva Collection Kit are stabilized and isolated for use with over-the-counter AncestryDNA Genetic Health Risk Tests. Saliva samples collected using the AncestryDNA Saliva Collection Kit can be transported and/or stored long term at ambient conditions.
The AncestryDNA Saliva Collection Kit consists of: saliva collection tube, funnel, cap, blister pack, collection bag with absorbent pad, return mailer, and Instructions for Use. The collection device consists of the saliva collection tube, funnel, and cap. The cap contains DNA stabilization solution. Saliva is delivered directly by spitting into the collection tube via the funnel. Once the user has provided the saliva sample, s/he removes the funnel from the saliva collection tube and affixes the cap. Affixing the cap by screwing on releases the stabilization solution. The user is then instructed to shake the tube for at least five seconds to mix the saliva sample with the stabilization solution. After collecting the saliva sample, the user places the closed saliva collection tube in the collection bag. The collection bag with the enclosed saliva collection tube is shipped to a designated Ancestry Genomics location for testing via the pre-addressed postage paid return mailer.
Acceptance Criteria for the AncestryDNA Saliva Collection Kit and Supporting Study
The AncestryDNA Saliva Collection Kit is intended for non-invasive collection, stabilization, transportation, and long-term storage of saliva samples for in vitro diagnostic testing of human DNA, specifically for use with the AncestryDNA Factor V Leiden Genetic Health Risk Test. The following acceptance criteria were established and demonstrated through analytical and user studies.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Analytical Performance | ||
| Reproducibility/Precision | Overall precision and per genotype point estimate > 99% agreement for genotyping with true variant status. | Lab 1: Overall Percent Agreement (OPA) = 100.00% (95% CI: 99.79 – 100.00%) |
| Lab 2: OPA = 100.00% (95% CI: 99.41 – 100.00%) | ||
| All operator teams combined: OPA = 100.00% (95% CI: 99.84 – 100.00%) | ||
| All AncestryDNA SCK lot combinations combined: OPA = 100.00% (95% CI: 99.84 – 100.00%) | ||
| Within-run repeatability: OPA = 100.00% (95% CI: 92.13 – 100.00%) | ||
| Inter-lab data at Lab 1 & 2: OPA = 100.00% (95% CI: 95.55 – 100.00%) | ||
| All "GG", "GA", "AA" genotypes: OPA = 100.00% (95% CI: 99.53 – 100.00%) | ||
| Analytical Sensitivity (LoD) | Lowest DNA concentration at which at least 95% of samples yielded the correct call. Concentrations between LoD and upper limit should produce genotypes concordant with bidirectional sequencing. | Limit of Detection (LoD): 1.53 ng/uL. |
| Upper limit of concentration: 50 ng/uL. | ||
| All genotyping attempts on samples with call rates ≥ 98% and concentrations between 1.53 ng/uL and 50 ng/uL produced genotypes 100% concordant with bidirectional sequencing. | ||
| Interfering Substances | ≥ 95% agreement with true variant status as determined by bi-directional sequencing for samples with endogenous, exogenous, and microbial interferents. | Endogenous Interference: 100% OPA for all tested interferents (PBS, Salivary α-amylase, Hemoglobin, IgA, Total Protein). |
| Exogenous Interference: 100% OPA for all tested interferents (Chicken, Alcohol, Mouthwash, Beef, Gum, Smoking) at various time points, where QC passed. | ||
| Microbial Interference: 100% OPA for all tested microbial interferents (S. epidermis, S. mutans, L. casei, A. odontolyticus, C. albicans) at low/normal and high concentrations. | ||
| Sample Volume Tolerance | For all samples that passed quality control for each collection volume (under-filled, normally filled, over-filled), ≥ 95% agreement with true variant status. | 100% OPA for all fill volumes (control, under, over) and all genotypes (Wild Type, Heterozygous, Variant). |
| Specimen Stability | Post-collection samples stored at 15°C to 30°C for up to 12 months should maintain performance. Transport at temperatures ranging from -29°C to 50°C and up to 85% RH should not impact performance. | Demonstrated through testing that post-collection samples can be stored at 15°C to 30°C for up to 12 months and transported at -29°C to 50°C and up to 85% RH while maintaining DNA integrity for genotyping. |
| Method Comparison | ||
| Accuracy (vs. Predicate) | > 99% agreement with true variant determination overall and per genotype tested, when comparing against bi-directional sequencing. | Overall Percent Agreement: 100% (95% CI: 98.2–100%) for all genotypes (GG, GA, AA) combined. |
| Per Genotype: GG (100%, 94.8–100%), GA (100%, 94.5–100%), AA (100%, 94.4–100%). | ||
| 100% concordance with true variant status for all 198 samples that passed QC. | ||
| Clinical Studies | ||
| User Comprehension | Flesch-Kincaid reading level of instructions for use shall meet or exceed the 8th grade threshold. High user satisfaction and understanding of instructions. Sufficient viable DNA yield from lay user collected samples. | Flesch-Kincaid reading level: 6.0 (total SCK instructions), 7.1 (text alone). This met the ≥ 8th grade threshold. |
| Viable DNA yield: 257 out of 271 (94.8%) submitted saliva samples passed all three evaluated failure points and had a sample call rate of ≥ 98%. | ||
| User feedback: 98.1% rated overall usability as somewhat easy or higher; 99.2% rated kit instructions as somewhat easy to understand or better; 98.1% indicated instructions were somewhat easy to follow or better; 99.6% found illustrations helpful. |
2. Sample Size Used for the Test Set and Data Provenance
The primary test set for demonstrating accuracy (Method Comparison) involved 209 donors (200 initial + 9 alternate).
Data Provenance: The study was conducted by a CLIA-certified laboratory (Ancestry Genomics' designated location) on collected saliva samples. The bi-directional sequencing for ground truth was performed by a third-party laboratory. The country of origin of the data is not explicitly stated, but the submission is to the U.S. FDA, suggesting the data is likely from the U.S. (or at least collected with U.S. regulatory oversight in mind). The study appears to be prospective as samples were collected specifically for the purpose of the study and then processed.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The ground truth for the test set (Factor V Leiden genotypes) was established using bi-directional sequencing analysis performed by a third-party laboratory. The document does not specify the number of individual experts (e.g., geneticists or laboratory personnel) involved in interpreting the sequencing results, nor their specific qualifications (e.g., years of experience). However, the use of "bi-directional sequencing" by a "third-party laboratory" implies a robust and standard method for genotype determination.
4. Adjudication Method for the Test Set
The document does not describe an adjudication method involving multiple human readers for discrepancies in the ground truth for the test set. The ground truth (true variant status) was determined solely by bi-directional sequencing.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not conducted. This device is a saliva collection kit, and the performance evaluation focuses on the analytical accuracy of DNA collection and subsequent genotyping, not on human interpretation of images or other data where AI might assist.
6. If a Standalone Study Was Done
Yes, a standalone performance study was done for the AncestryDNA Factor V Leiden GHR Test in combination with the AncestryDNA Saliva Collection Kit. The reported performance metrics (reproducibility, analytical sensitivity, interference, sample volume tolerance, and accuracy) directly reflect the algorithm's (genotyping test's) ability to correctly identify genotypes from samples collected by the device, without human intervention in the genotype determination process itself. The user comprehension study also evaluated the standalone usability of the collection kit by lay users.
7. The Type of Ground Truth Used
The ground truth used for determining the true variant status of the Factor V Leiden genotype was bi-directional sequencing. This is considered a gold standard method for confirming genetic sequences.
8. The Sample Size for the Training Set
The document does not provide information regarding a specific "training set" sample size for the AncestryDNA Factor V Leiden GHR Test algorithm. It describes analytical and clinical validation studies for the device and its compatibility with the GHR test. Since this is for a collection kit and an established genotyping method (Illumina Infinium array platform), it's less likely to involve a distinct "training set" in the same way machine learning models typically do for image analysis, for example. The genotyping methodology itself has inherent validation processes, and the studies here validate the use of the collection kit with that methodology.
9. How the Ground Truth for the Training Set Was Established
As a specific "training set" is not explicitly mentioned or relevant in the common AI/ML sense for this type of device (a collection kit and a genotyping test on an array platform), the method for establishing ground truth for a training set is not applicable and therefore not described in the document.
§ 862.1675 Blood specimen collection device.
(a)
Identification. A blood specimen collection device is a device intended for medical purposes to collect and to handle blood specimens and to separate serum from nonserum (cellular) components prior to further testing. This generic type device may include blood collection tubes, vials, systems, serum separators, blood collection trays, or vacuum sample tubes.(b)
Classification. Class II.