Speaking at a meeting of biotechnologists in Denver last week, the Rev. John C. Fletcher nicely summarized the social challenge of genetic engineering. ''The dynamics of genetics were, and are, thought to be - by some - directed by divinity,'' he said, adding that ''this belief is very strong. It's still there and it has to be dealt with.''
However remote the technical possibility, there is indeed a widespread fear that genetic engineers will one day try to redesign human beings. Mr. Fletcher, an Episcopal priest, encountered this fear in his work as an adviser on ethics for the US National Institutes of Health. Hence his warning to those attending last week's meeting of the Industrial Biotechnology Association that such deep-seated feelings cannot be ignored.
Many of those at the meeting, however, as well as many other geneticists and biotechnologists, would like to ignore an earlier resolution sent to Congress on June 8 by some 64 religious leaders and a few scientists. It urges Congress to ban attempts to tinker with human genes in reproductive cells. In other words, no tampering with human ''design.''
That resolution strikes many as ill-conceived and ill-timed - and may well be. A presidential commission late last year turned in a comprehensive study of genetic engineering, which urged that a watchdog committee be set up to monitor its trends and applications. The commission had itself been established in response to an appeal from religious leaders that more attention be paid to the ethical aspects of genetic engineering. Rep. Albert Gore Jr. (D) of Tennessee immediately introduced legislation, now pending, to establish such a commission.
Thus the June 8 resolution seems superfluous. True, it calls for a ban on certain work with human genes rather than just a monitoring of trends. But since there is no immediate prospect of anyone's trying to redesign humans, the distinction seems meaningless. Furthermore, many experts worry that such a ban would also stop work on ways to correct genetic ''defects'' which medical experts link with certain diseases. Religious leaders who signed the resolution say this was not their intent.
It now is apparent that the June 8 resolution, and a press release that accompanied it, are largely the work of Jeremy Rifkin, a social activist who has taken on genetic engineering among other causes. He would like to ban genetic engineering outright, as he explains in his recent book ''Algeny.'' Many geneticists, such as those attending the Denver meeting, now tend to dismiss the resolution as Rifkin propaganda - although the Rev. Mr. Fletcher warned against so simplistic a view.
Regardless of the specific merits of the resolution, it reflects a concern of many people. Not only do they wonder about the technical possibilities. They also wonder about what should and should not be allowed in human gene engineering - and about how such work is to be controlled. Mr. Fletcher is correct in calling their concern ''an honest question'' that ''deserves an honest answer.'' Religious leaders and others involved with this issue would serve the public better by establishing a forum where the question can be thoroughly discussed - rather than by trying to have Congress suppress some aspects of biological research. Antarctic not melting
Concern that a warming trend due to carbon dioxide is melting Antarctic ice seems premature. Study of old records, coupled with evidence from environmental satellites, now shows that what seemed to some scientists to be a possibly dangerous meltback has reversed itself.
Were Antarctic ice to melt substantially, the level of the world's seas could rise enough to flood many coastal areas. Hence the concern that arose two years ago when George Kukla and J. Gavin of Columbia University's Lamont-Doherty Geological Observatory reported that the Antarctic ice pack had shrunk during the 1970s. They suggested that warming due to the heat-trapping action of atmospheric carbon dioxide might have been responsible. Carbon dioxide, released when fossil fuel burns, is building up in the air because of increased fuel use.
J. C. Comiso, C. L. Parkinson, and Jay Zwally of the Goddard Laboratory for Atmospheric Sciences have recently pointed out in Science, however, that the ice decline of the '70s was only a swing of a long-established cycle. That face is apparent, they say, in studying records going back to the 18th and 19th centuries. The three scientists suggest that recent changes ''may simply have been a natural fluctuation.''
Their finding does not rule out a warming effect due to carbon dioxide buildup. But there seems little evidence that any such warming has yet affected the Antarctic sea ice. Rocks on Venus
Pictures and data sent back by the Soviet probes Venera 13 and 14, which landed on Venus in March last year, show what appear to be sedimentary rocks on that sizzling hot planet.
Ten Soviet scientists and an American visitor (L.B. Ronca of Wayne State University), writing in Science, report that in the present Venusian surface environment (with temperatures hot enough to melt lead) sediments to form rock could not be deposited from water. But winds or other dry processes might well accumulate loose material that could be solidified.
The scientists note that the layered formations show ripple marks, erosion, and curving fractures typical of sedimentary rock. Again, typically, they have little bearing strength and are highly porous.
Meanwhile, two more Soviet probes - Venera 15 and 16 - are heading for Venus. Launched on June 2 and 7, they should arrive at Venus this fall. There they will orbit the planet to carry out measurements of its atmosphere and surface.