Ordering an add-on test

An "Add-on Test" is a request to add an additional test to a previously tested patient specimen. 

Sample sufficiency

In some cases, HNL Genomics (CTGT) may not have enough DNA remaining from the previously tested specimen to perform the add-on test. HNL Genomics (CTGT)  highly recommends contacting us to confirm that there is a sufficient amount of DNA prior to ordering an add-on test. If an add-on test request is received and there is not enough DNA to perform the test, phone and/or email notification will be provided within 24 hours of receipt of the add-on request. For cases with an insufficient amount of DNA, a new sample is required in order to perform the test.  Add-on tests may be requested for all specimen types, including prenatal specimens.

Requisition form

HNL Genomics (CTGT) does not provide a separate requisition form for add-on tests. To order an add-on test, complete our standard requisition form, including payment information, and note in the “Special Test Instructions” section on the last page of the requisition form that the order is for an add-on test.  Fax the completed requisition form to HNL Genomics (CTGT) at 484-244-2904. 

For institutional billing, HNL Genomics (CTGT) highly recommends that the add-on test is requested through the institutional Sendout Department, which initially sent the patient sample. An add-on test CANNOT be properly processed, if the Sendout Department has not been notified. HNL Genomics (CTGT) will begin testing when a requisition form is received from the Sendout Department. 

Turnaround time

Our standard turnaround times (approximately 1-2 weeks for Sanger sequencing, approximately 2-3 weeks for deletion/duplication tests and 2-4 weeks for NextGen sequencing) also apply to add-on tests.

The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. HNL Lab Medicine strongly recommends confirmation of CPT codes with third-party payors and/or the AMA. We assume no responsibility for billing errors due to reliance upon CPT codes provided by HNL Lab Medicine.


October 28, 2022

Non-Hodgkin Lymphoma FISH Panel Now Available

B-cell lymphoma is a large group of heterogenous disorders and comprises a majority of non-Hodgkin lymphomas.
Read More
October 20, 2022

Genetic testing for Familial Transthyretin Amyloidosis (TTR) NOW AVAILABLE In-House

Hereditary amyloidosis is a life-threatening disorder that can lead to peripheral neuropathy and heart failure.
Read More
August 08, 2022

Familial hypercholesterolemia (FH)

Familial hypercholesterolemia (FH) is a genetic disorder that increases the likelihood of having coronary heart disease at a younger age. Learn about how to determine if you have hypercholesterolemia and what actions you can take to create better outcomes!

Read More
April 11, 2022

Genome Sequencing: A Vital Tool Used in Identifying and Tracking New COVID-19 Variants

Genome sequencing is reading or decoding the complete genetic information i.e. “Genome” of an organism that is encrypted in the form of a very long string called DNA made up of 4 letters, A, T, G, and C. The genome of an organism essentially determines their physical characteristics and ...
Read More
March 03, 2022

The Effect of Genetics on Individual Heart Health: Early Identification of FH Variations to Optimize Treatment

Test must be ordered by a Physician.

Familial hypercholesterolemia (FH) is a genetic disorder that is characterized by abnormally high blood levels of low-density lipoprotein (LDL) cholesterol, sometimes referred to as "bad cholesterol". This condition affects an estimated 1 in 250 people, and increases the likelihood of developing cardiovascular disease. In fact, FH is estimated to be the cause of 2-3% of heart attacks in individuals younger than age 60.

Read More