COLD SPRING HARBOR, N.Y. -- Two years and two weeks ago, ateam of clinical gene therapists at the National Institutes ofHealth put back into the bloodstream of a 4-year-old girl abillion or so of her own T cells, after transfecting them withthe gene that expresses adenosine deaminase (ADA).

For lack of that enzyme, this first-ever gene therapy recipientsuffered from a rare but fatal metabolic disorder, severecombined immunodeficiency disease G-SCID, the "boy-in a-bubble" syndrome.

A few months later, a second SCID patient, this time a girl of9, began receiving the same gene-restoring treatment. On Sept.14, both girls, now 6 and 11, were guests of honor at a two-year anniversary party organized by the NIH gene-therapy staffto celebrate the successful outcome of their trail-blazingexperiment.

The first patient was enrolled in public school a year ago, andaccording to R. Michael Blaese, her lead physician at NIH, "Shehas had no more infections than any of her classmates." Thesecond's recovery has been equally favorable.

Blaese reported these success stories last week to aninternational meeting here at Cold Spring Harbor Laboratory.This gene therapy "summit," as its co-organizer, W. FrenchAnderson, characterized the event to BioWorld, broughttogether 326 researchers, more than 100 of them from 20countries of Europe and Asia.

Among these attending were representatives of some 17 majorpharmaceutical and chemical companies, plus 22 biotechnologyR&D firms. Anderson counts "at least 11" of the lattercompanies as "exclusively dedicated to gene-therapy researchas a primary goal."

In the past two years, human gene therapy has proliferatedfrom a visionary attempt to cure genetic disorders such asSCID to a plausible ploy for treating virtually every disease inthe medical dictionary G- from AIDS, atherosclerosis andarthritis to cancers and Parkinson's disease.

As of last week, 37 gene-therapy clinical-trial protocols hadbeen approved by the FDA and the NIH Recombinant-DNAAdvisory Committee. About half of them G- beginning with thenow-historic SCID girls G- aim at gene-replacement with acurative intent.

The 19 remaining involve implanting marker genes asprecursor strategies to track and evaluate gene-therapytechniques in human subjects. Five of this second group arebeing conducted at NIH, 12 at seven U.S. teaching hospitals, andone in Lyons, France.

-- David N. Leff Science Editor

(c) 1997 American Health Consultants. All rights reserved.