Anticipation in Crohn's disease may be influenced by gender and ethnicity of the transmitting parent.
OBJECTIVE
We sought to examine whether anticipation (an earlier age of onset in succeeding generations) is observed in Crohn's disease (CD) patients within the New York metropolitan area, and whether there are differences in the degree of anticipation with respect to gender and ethnicity of the affected parent.


METHODS
Sixty-one parent-child pairs both affected by CD were identified; about half of the pairs were of Ashkenazi Jewish descent. An additional 17 pairs of second-degree relatives with CD were also identified. The intergenerational difference in age at diagnosis (AAD) was used to perform regression analysis and the degree of anticipation among subsets of patients separated on the basis of gender and ethnicity of the transmitting parent was determined.


RESULTS
The AAD was consistently (90% of the time) lower in the younger member of the 61 parent-child pairs (35.3+/-1.6 yr vs 20.8+/-1.1 yr, p = 0.0001). Furthermore, the degree of anticipation was significantly greater for father-child pairs (20.6+/-3.2 yr) than for mother-child pairs (11.7+/-2.1 yr). However, when the patient population where the parent had an AAD of < 28 was analyzed separately, there was a lack of clear-cut evidence of anticipation in the population as a whole. Only when the population was subdivided by ethnicity was there convincing evidence of anticipation in the Jewish population.


CONCLUSIONS
Ascertainment bias may be responsible for the apparent anticipation observed in the CD population as a whole or in the nonJewish CD subgroup. However, the Jewish CD population displays strong evidence of anticipation even after correction for ascertainment bias.
Heresbach
D
D
Department of Environmental Medicine, North Shore University Hospital/New York University School of Medicine, Manhasset 11030, USA.
Gulwani-Akolkar
B
B
Lesser
M
M
Akolkar
P N
PN
Lin
X Y
XY
Heresbach-Le Berre
N
N
Bretagne
J F
JF
Katz
S
S
Silver
J
J
D000328:Adult; D020132:Anticipation, Genetic; D015982:Bias; D003424:Crohn Disease / Q000208:ethnology* / Q000235:genetics*; D005260:Female; D006801:Humans; D007585:Jews / Q000235:genetics*; D008297:Male; D012727:Sex Characteristics