‘genetic work on animal viruses is very smafl

September 30, 1957

Dear Jims ne

IL just thought I should let you know that Esther and I
very likely will be returning home via India and Europe
rather than Califormia. This is not quite settied, and I
will send you a definite itinerary in a couple of weeks; however
if anything has come up that you might be holding for our pos-
sible stopover in Berkeley, it would be better to deal with -

it by mail. = -

We will remain in Melbourm, where we are comfortably settled,
till the end of October, and, if we return westward, will get
home about Thanksgiving, ~~~ Ts me
'- If we go to India, it will be in response to a formal invi-
tation from the Government (Atomic Energy Commission in Bombay)
and this sounds like an unusual opportunity. - oo

- an oOo re

My work here has been working out better than I could have
reasonably expected, largely because Burnet hae assigned one of
his personal assistants to work with me during my vigsit. This
has made it possible for me to get my hands deep into influensa
virus genetics, and I have been learning a great deal, first
hand, At the moment, I am trying to work out some improved,
Belective techniques for recombination analysis, principally
with the use of mucoprotein inhibitors. There is also a rather

interesting problem an dominance and autonomous action of
virus alleles in phenotypic mixing: in the yield from a

mixedly infected oell, the Phenotype of the particles is

‘determined by the whole cell, not the individual particles.
’ Thus, as was already known, most of the particles can be

neutrakized by wrtuerx antiserum for either component; on
the other hand, the phenotype qua reaction to inhibitory |
mucoids seeme to show dominance of resistance. Thus, for

two mucoids, m and Bs, the pheumtyperefrths two types of

experimental yields: —-
__ ma? gt / w® 28 as well as “mt gS / m® g*
are both phenotypically m? s™, The work with this bug

does go fast enough that there is some hope of finishing up
@ segment before my leaving. Unfortunately Burnet wimself,

after 20 years of nothing mm else is getting) rather weary

of flu, and is moving over to problems of te itechanism
of antibody determination & the number of jabs doing sound

  

‘With best regards,

Joshua Lederberg