Guillermo Lopez
Guillermo Lopez is a provider specialising in Ph.D. Medical Genetics in San Antonio, TX, registered under NPI 1790422087. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 1337 BARCLAY ST, San Antonio, TX 78207. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 456078567897 | TX | Ph.D. Medical Genetics primary |
This provider holds licence 456078567897 issued in TX. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Medical Genetics, Ph.D. Medical Genetics covers
A medical geneticist works in association with a medical specialist, is affiliated with a clinical genetics program, and serves as a consultant to medical and dental specialists. NUCC Health Care Provider Taxonomy, code 170100000X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1790422087 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | May 18, 2022 |
| Last updated | May 18, 2022 |
| Status | Active |
| Sole proprietor | Yes |
| Practice address |
1337 BARCLAY ST San Antonio, TX 78207 (210) 851-0698 |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 7 | 9 | 0 | 4 | 2 | 2 | 0 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 7 | 9 | 0 | 8 | 2 | 4 | 0 | 7 |
Sum = 63 · next multiple of 10 = 70 · check digit = 7 · actual last digit = 7
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.