The aim of this paper is to study the inheritance pattern of ear tip-barrenness trait in maize （Zea mays L.）. Ear tipbarrenness trait in maize can be classified into two types, tip-barren and tip-barrenless. Two inb...The aim of this paper is to study the inheritance pattern of ear tip-barrenness trait in maize （Zea mays L.）. Ear tipbarrenness trait in maize can be classified into two types, tip-barren and tip-barrenless. Two inbred lines, lx01-3 （tipbarrenless type）, wx04-1 （tip-barren type）, and their F1, F2, BC1, BC2 generations were analyzed on their ear tip-barrenness types. Results showed that F1 was tip-barren type; the ratio of tip-barren type versus tip-barrenless type followed a 12.78： 1 ratio in F2 segregation population and a 2.75：1 ratio in BC1. Z2 test indicated that the trait of ear tip-barrenness type followed an inheritance pattern of 2 duplicate dominant genes. SPSS analysis indicated that the trait of ear tip-barrenness length is of abnormal distribution. Above results mean that： （1） The trait of maize ear tip-barrenness type is controlled by 2 duplicate dominant genes; tip-barren type is dominant over tip-barrenless type; （2） the trait of tip-barrenness length is a quantitative character controlled by polygene with major genes expected.展开更多
Background Congenital cataract is a sight-threatening disease that affects about 1-6 cases per 10000 live births and causes 10%-30% of all blindness in children About 25% of all cases are due to genetic defects...Background Congenital cataract is a sight-threatening disease that affects about 1-6 cases per 10000 live births and causes 10%-30% of all blindness in children About 25% of all cases are due to genetic defects We identified autosomal dominant congenital coralliform cataracts-related genetic defect in a four-generation Chinese family Methods Complete ophthalmological examinations were performed prior to lens extraction Lens samples were then studied by electron microscopy Genomic DNA from family members were examined using whole-genomic linkage analysis, with two-point logarithm of odds (LOD) scores calculated using the Linkage program package (version 5 1) Mutation analysis of candidate genes was performed by direct sequencing Finally, a three-dimensional protein model was predicted using Swiss-Model (version 2 0) Results Eleven of the 23 examined individuals had congenital cataracts Ultrastructure studies revealed crystal deposits in the lens, and granules extensively dispersed in transformed lens fiber cells The maximum two-point LOD score, 3 5 at θ=0 1, was obtained for the marker D2S325 Mutation analysis of the γ-crystallin (CRYG) gene cluster identified a mutation (P23T) in exon 2 of γD-crystallin (CRYGD) Protein structure modeling demonstrated that the P23T mutation caused a subtle change on the surface of the γD protein Conclusions The results suggest that the coralliform cataract phenotype is due to a mutated CRYGD gene, and that this sequence change is identical to one reported by Santhiya to be related to another distinct clinical condition, lamellar cataract This study provides evidence that this same genetic defect may be associated with a different phenotype This is the first report identifying the genetic defect associated with an autosomal dominant congenital coralliform cataract展开更多
文摘The aim of this paper is to study the inheritance pattern of ear tip-barrenness trait in maize （Zea mays L.）. Ear tipbarrenness trait in maize can be classified into two types, tip-barren and tip-barrenless. Two inbred lines, lx01-3 （tipbarrenless type）, wx04-1 （tip-barren type）, and their F1, F2, BC1, BC2 generations were analyzed on their ear tip-barrenness types. Results showed that F1 was tip-barren type; the ratio of tip-barren type versus tip-barrenless type followed a 12.78： 1 ratio in F2 segregation population and a 2.75：1 ratio in BC1. Z2 test indicated that the trait of ear tip-barrenness type followed an inheritance pattern of 2 duplicate dominant genes. SPSS analysis indicated that the trait of ear tip-barrenness length is of abnormal distribution. Above results mean that： （1） The trait of maize ear tip-barrenness type is controlled by 2 duplicate dominant genes; tip-barren type is dominant over tip-barrenless type; （2） the trait of tip-barrenness length is a quantitative character controlled by polygene with major genes expected.
文摘Background Congenital cataract is a sight-threatening disease that affects about 1-6 cases per 10000 live births and causes 10%-30% of all blindness in children About 25% of all cases are due to genetic defects We identified autosomal dominant congenital coralliform cataracts-related genetic defect in a four-generation Chinese family Methods Complete ophthalmological examinations were performed prior to lens extraction Lens samples were then studied by electron microscopy Genomic DNA from family members were examined using whole-genomic linkage analysis, with two-point logarithm of odds (LOD) scores calculated using the Linkage program package (version 5 1) Mutation analysis of candidate genes was performed by direct sequencing Finally, a three-dimensional protein model was predicted using Swiss-Model (version 2 0) Results Eleven of the 23 examined individuals had congenital cataracts Ultrastructure studies revealed crystal deposits in the lens, and granules extensively dispersed in transformed lens fiber cells The maximum two-point LOD score, 3 5 at θ=0 1, was obtained for the marker D2S325 Mutation analysis of the γ-crystallin (CRYG) gene cluster identified a mutation (P23T) in exon 2 of γD-crystallin (CRYGD) Protein structure modeling demonstrated that the P23T mutation caused a subtle change on the surface of the γD protein Conclusions The results suggest that the coralliform cataract phenotype is due to a mutated CRYGD gene, and that this sequence change is identical to one reported by Santhiya to be related to another distinct clinical condition, lamellar cataract This study provides evidence that this same genetic defect may be associated with a different phenotype This is the first report identifying the genetic defect associated with an autosomal dominant congenital coralliform cataract
