[susan53]

Frequent is an adjective which can be used with either countable or uncountable nouns. For example :

1) FREQUENT + countable noun - either singular or plural

a) This is a FREQUENT reminder of...

b) This is a is a FREQUENT pitfall in this sort of arrangement

c) We started to get fed up with his FREQUENT visits.

d) The most FREQUENT excuse for this is...


2) FREQUENT + uncountable noun


a) FREQUENT use (especially of caffeine-containing medications) can lead to an increase in headaches.

b) Reads with difficulty, and only with FREQUENT recourse to the dictionary

c) This was what determined an attitude of fear in Spanish society — independent of the FREQUENT courage of individuals — which...

d) This still left him subject to FREQUENT despair and loneliness.


A lot of nouns can be used either countably or uncountably - often with different meanings - as with use (uncountable - see 2a above) (= utilisation) and use countable (different ways of using - eg Dictionaries have a number of uses).

In your sentence, mutation makes much more sense conceptualised as an abstract process, so Frequent mutation of the genes is much more likely than mutations. In something like the following, however, either would be possible:

Frequent genetic mutations were observed in the plants from generation to generation..
Frequent genetic mutation was observed in the plants from generation to generation..

Ironically, the mistakes in this extract weren't in the use of mutation, but in the second sentence which is has a number of problems and should read :

Since the droppings from diseased chickens may contain the virus, be sure to wash your hands with soap and water after any contact with chickens.

- droppings (always plural) = excreta, which can only come from the bird, not the meat - so chickens and not chicken.
- contacting = communicating with. Here the writer clearly means "touching" so the expression should be (have) contact with , which covers all types of contact, whether communicative or physical.