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Presentation, Heritability, and Genome-Wide Linkage Analysis of
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the Midchildhood Growth Spurt in Healthy Children from the
4 Fels Longitudinal Study
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6 bradford towne, 1,2 kimberly d. williams, 1 john blangero, 3 stefan a.
7 czerwinski, 1 ellen w. demerath, 4 ramzi w. nahhas, 1 thomas d. dyer, 3
8 shelley a. cole, 3 miryoung lee, 1 audrey c. choh, 1 dana l. duren, 1,5
9 richard j. sherwood, 1,6 william cameron chumlea, 1,2 and roger m.
10 siervogel 1,2
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12 Abstract Growth is a complex process composed of distinct phases over the
course of childhood. Although the pubertal growth spurt has received the most [First Page]
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attention from auxologists and pediatricians, the midchildhood growth spurt
14 [623], (1)
has been less well studied. The midchildhood growth spurt refers to a rela-
15 tively small increase in growth velocity observed in some, but not necessarily
16 all, children in early to middle childhood. If present, the midchildhood growth
17 spurt typically occurs sometime between the ages of 4 and 8 years, well be- Lines: 0 to 42
18 fore the onset of the far more pronounced pubertal growth spurt. In this study ———
19 we used a triple logistic curve-fitting method to fit individual growth curves 0.89745pt PgVar
20 to serial stature data from 579 healthy participants in the Fels Longitudinal ———
21 Study, 479 of whom have been genotyped for about 400 short tandem repeat Long Page
22 (STR) markers spanning the genome. We categorized individuals according to
the presence or absence of a midchildhood growth spurt and then conducted PgEnds: TEX
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heritability and genome-wide linkage analyses on the dichotomous trait. In
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the total sample of 579 individuals, 336 (58%) were found to have evidence
25 of having had a midchildhood growth spurt. There was a marked sex differ-
[623], (1)
26 ence in presence of the midchildhood growth spurt, however, with 232 of the
27 293 males (79%) having had a midchildhood growth spurt but just 104 of
28 the 286 females (36%) having had one. Presence of a midchildhood growth
29 spurt was found to have a significant heritability of 0.37 ± 0.14 ( p = 0.003).
30 Two quantitative trait loci with suggestive LOD scores were found: one at 12
31 cM on chromosome 17p13.2 (LOD = 2.13) between markers D17S831 and
32 D17S938 and one at 85 cM on chromosome 12q14 (LOD = 2.06) between
33 markers D12S83 and D12S326.
34 1
Lifespan Health Research Center, Department of Community Health, Boonshoft School of Medicine,
35 Wright State University, 3171 Research Blvd., Dayton, OH 45420.
36 2
Department of Pediatrics, Boonshoft School of Medicine, Wright State University, Dayton, OH.
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