[Characteristics of refractive status of mutant Lumican transgenic mice]

To investigate the change of refractive status in transgenic mice with mutant Lumican (bright proteoglycan) gene at different ages.

Experimental Study. Fifty-four 3-week-old with mutant Lumican gene (cDNA 596T > C) mice (27 male and 27 female) were randomly divided into 9 groups (n = 6, half male and half female) by random number table. One group (3-week-old) was randomly chosen and measured the refractive status by retinoscopy after mydriasis. Measurement of other groups were repeated the method above respectively in the fourth, fifth, sixth, eighth, tenth, twelfth, sixteenth, and twentieth week. Differences of diopter between right and left eye and between male and female were compared within each group by paired t test. The differences of mice's diopters in different age were compared by Kruskal-Wallis H test. Pairwise comparisons were acquired by Mann-Whitney U test.

There were no statistic difference of diopters between binoculus: The mice's diopters of right and left eyes were respective measured in the twentieth week (1.50 ± 0.45) D and (1.25 ± 0.42) D (t = -0.889, P > 0.05), The mice's diopters of right and left eyes were respective measured in the third week (-2.50 ± 2.59) D and (-2.50 ± 4.32) D (t = 0.000, P > 0.05); There were no statistic difference of diopters between different genders: The mice's diopters of female and male were respective measured in the third week (-0.5 ± 3.83) D and (-4.17 ± 1.94) D, (t = 2.079, P > 0.05), The mice's diopters of female and male were respective measured in the twelfth week (1.50 ± 0.84) D and (1.50 ± 1.87) D (t = 0.000, P > 0.05); Analysis of binocular diopters revealed significant differences among nine groups (H = 20.910, P < 0.05). Diopters measured in the third week (-2.50 ± 3.40D) and the sixth week (+3.25 ± 2.67) D had statistical difference (Z = -3.259, P < 0.001). There were no statistical significance between other groups (P > 0.001).

Characteristics of diopters gathered from mice with Lumican gene mutation at different weeks are summarized as follows: Myopia could be observed in the third week. And this situation of myopia was gradually transformed into hyperopia with aging. The maximum hyperopic diopter was observed at 6th-week-old mice. From the eighth to twentieth week, the degree of hyperopic diopter gradually decreased and stabilized.