A method is disclosed for the direct synthesis of double stranded DNA molecules of a variety of sizes and with any desired sequence. The DNA molecule to be synthesis is logically broken up into smaller overlapping DNA segments. A maskless microarray synthesizer is used to make a DNA microarray on a substrate in which each element or feature of the array is populated by DNA of a one of the overlapping DNA segments. The DNA segments are released from the substrate and held under conditions favoring hybridization of DNA, under which conditions the segments will spontaneously hybridize together to form the desired DNA construct. This method makes possible the remote assembly of DNA sequence, through a process analogous to facsimile transmission of documents, since the information on DNA to be made can be transmitted remotely to an instrument which can then synthesize any needed DNA sequence from the information.