for people ages 18-80 (full criteria)
healthy people welcome
at San Francisco, California
study started
estimated completion
Alan Wu, PhD



The objective of this study is to recruit healthy adult identical and fraternal twins for the collection of one teaspoon of blood to be sent to the Clinical Lab at San Francisco General Hospital. The serum will be tested to determine the reference range for free light chains.

Official Title

Normal Range Study for Free Light Chains in Blood Among Identical or Fraternal Twins


Serum free light chains are used to assist in the diagnosis of multiple myeloma. The test measures kappa (K) and lambda (L) chains, and the calculation of the ratio of kappa to lambda (K/L). Previous studies have shown that the K/L ratio does not change over time (1 year). The hypothesis of this study is that healthy twins will have a K/L ratio that are close to each other in value, suggesting that this ratio is geneticallyl linked.


Multiple Myeloma free light chains healthy twins


You can join if…

Open to people ages 18-80

  • Healthy subjects 18-80 years.
  • Must be an identical or fraternal twin (both must be recruited)

You CAN'T join if...

- Symptoms suggestive of multiple myeloma (e.g., renal insufficiency, anemia, bone pain)


  • San Francisco General Hospital accepting new patients
    San Francisco California 94306 United States

Lead Scientist

  • Alan Wu, PhD
    Alan Wu has several areas of expertise. He is chief of the clinical chemistry and toxicology laboratories at San Francisco General Hospital. In this capacity, his clinical and research laboratory conducts testing for routine analytes in blood, urine and cerebral spinal fluid for electrolytes, metabolites, hormones, proteins, and biomarkers.


accepting new patients
Start Date
Completion Date
University of California, San Francisco
Study Type
Last Updated