Table 4.

Frequencies of CD16A F/F homozygosity

Populations	Number donors			% F/F	95% confidence limits+
	F/F	F/V or V/V	All
CFS patients	10	1	11	90.9	58.7–99.8%
Non-CFS family members	18	4	22	81.8	59.7 –94.8%
Unrelated healthy donors	3	13	16	18.8	4–45.6%
CFS family parents, highest possible %F/F#	8	2	10	80@	44.4–97.5%
CFS family parents, lowest possible %F/F#	5	5	10	50.0	18.7–81.3%
Reference Group: Northern European origin^	385	534	919	41.9	38.7–45.2%

⁺Binomial “exact” calculations of the confidence intervals for proportions

^#Ten CFS family parents: living 5 F/F, 2 F/V, and 0 V/V; 3 deceased.

^@P <0.05, for 8 or more F/F, calculated with 0.419 as the probability that a parent will be F/F.

^{^}From reference (40); the FCGR3A allele encoding V158 CD16A had a frequency of 0.363.