<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM ILLUMINA
INC.'S BALANCE SHEETS AS OF DECEMBER 31, 1999 AND JUNE 30, 2000 AND RELATED
STATEMENTS OF OPERATIONS AND CASH FLOWS FOR THE THREE MONTHS ENDED JUNE 30, 1999
AND 2000 AND FOR THE SIX MONTHS ENDED JUNE 30, 1999 AND 2000 AND IS QUALIFIED IN
ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>

                                                  
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-2000
<PERIOD-START>                             JAN-01-1999             JAN-01-2000
<PERIOD-END>                               JUN-30-1999             JUN-30-2000
<CASH>                                      21,164,114              19,595,187
<SECURITIES>                                11,924,163              11,544,891
<RECEIVABLES>                                   49,818                  38,287
<ALLOWANCES>                                         0                       0
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                            33,493,045              32,072,232
<PP&E>                                         296,286               1,621,839
<DEPRECIATION>                                 (4,972)               (131,055)
<TOTAL-ASSETS>                              33,894,658              33,694,192
<CURRENT-LIABILITIES>                          612,408               1,415,555
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                 37,397,998              37,397,998
<COMMON>                                        51,391                  64,213
<OTHER-SE>                                 (5,417,139)             (9,954,819)
<TOTAL-LIABILITY-AND-EQUITY>                33,894,658              33,694,192
<SALES>                                              0                       0
<TOTAL-REVENUES>                               129,863                  78,652
<CGS>                                                0                       0
<TOTAL-COSTS>                                1,335,533               5,837,908
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                   0                       0
<INCOME-PRETAX>                                      0                       0
<INCOME-TAX>                                    88,195                 489,713
<INCOME-CONTINUING>                        (1,117,475)             (5,269,543)
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                               (1,117,475)             (5,269,543)
<EPS-BASIC>                                     (0.95)                  (2.05)
<EPS-DILUTED>                                   (0.95)                  (2.05)