Table 3.
Effect of donor variables on cluster volume from mixed effects linear regression. The coefficient is the absolute change from the reference group.
Variable | Mean cluster volume (µm3) | SD | Without adjustment for CR1 copy number | With adjustment for CR1 copy number | ||||
---|---|---|---|---|---|---|---|---|
Coefficient | Standard error | t value | Coefficient | Standard error | t value | |||
Combined genotype# | ||||||||
1a | 0.468 | 0.146 | Reference | NA | NA | Reference | NA | NA |
2a | 0.476 | 0.127 | 0.012 | 0.029 | 0.400 | 0.016 | 0.022 | 0.717 |
2b | 0.502 | 0.160 | 0.035 | 0.054 | 0.658 | −0.029 | 0.042 | −0.708 |
Sl component alone | ||||||||
Sl1/Sl1 | 0.468 | 0.146 | Reference | NA | NA | Reference | NA | NA |
Sl2/Sl2 | 0.478 | 0.130 | 0.014 | 0.029 | 0.475 | 0.012 | 0.022 | 0.552 |
McC component alone | ||||||||
McC a /McC a | 0.474 | 0.131 | Reference | NA | NA | Reference | NA | NA |
McC b /McC b | 0.502 | 0.160 | 0.027 | 0.049 | 0.545 | −0.041 | 0.038 | −1.08 |
Gender | ||||||||
Female | 0.486 | 0.126 | Reference | NA | NA | Reference | NA | NA |
Male | 0.468 | 0.137 | −0.022 | 0.024 | −0.895 | −0.011 | 0.019 | −0.584 |
ABO blood group | ||||||||
O | 0.469 | 0.137 | Reference | NA | NA | Reference | NA | NA |
A | 0.476 | 0.100 | 0.008 | 0.030 | 0.264 | 0.029 | 0.023 | 1.275 |
B | 0.502 | 0.164 | 0.032 | 0.033 | 0.994 | 0.057 | 0.025 | 2.305 |
AB | 0.451 | 0.083 | −0.022 | 0.063 | −0.355 | 0.012 | 0.047 | 0.262 |
α+thalassaemia genotype | ||||||||
αα/αα | 0.493 | 0.139 | Reference | NA | NA | Reference | NA | NA |
−α/αα | 0.475 | 0.136 | −0.022 | 0.027 | −0.805 | −0.008 | 0.021 | −0.401 |
−α/−α | 0.444 | 0.109 | −0.051 | 0.033 | −1.54 | −0.017 | 0.026 | −0.654 |
Sickle cell (HbS) genotype | ||||||||
AA | 0.472 | 0.133 | Reference | NA | NA | Reference | NA | NA |
AS | 0.500 | 0.133 | 0.031 | 0.035 | 0.880 | 0.029 | 0.027 | 1.089 |
Age (years) Change in cluster volume with each additional year of age | −0.002 | 0.004 | −0.560 | −0.005 | 0.003 | −1.411 | ||
CR1 copy number Change in cluster volume with each additional 100 CR1 copies per cell | NA | NA | NA | 0.039 | 0.004 | 9.446 |
# 1a = Sl1/Sl1, McC a /McC a genotype, 2a = Sl2/Sl2, McC a /McC a genotype, 2b = Sl2/Sl2, McC b /McC b. SD, standard deviation. NA, not applicable.