A novel and de novo splice-donor site mutation in intron 3 of the GH-1 gene in a patient with isolated growth hormone deficiency

A heterozygous de novo G to A point mutation in intron 8 at the +5 position of the splice donor site of the gene for the pro alpha 1(I) chain of type I procollagen, COL1A1, was defined in a patient with type IV osteogenesis imperfecta. The splice donor site mutation resulted not only in the skipping of the upstream exon 8 but also unexpectedly had the secondary effect of activating a cryptic splice site in the next upstream intron, intron 7, leading to re-definition of the 3′ limit of exon 7. These pre-mRNA splicing aberrations cause the deletion of exon 8 sequences from the mature mRNA and the inclusion of 96 bp of intron 7 sequence. Since the mis-splicing of the mutant allele product resulted in the maintenance of the correct codon reading frame, the resultant pro alpha 1(I) chain contained a short non-collagenous 32-amino-acid sequence insertion within the repetitive Gly-Xaa-Yaa collagen sequence motif. At the protein level, the mutant alpha 1(I) chain was revealed by digestion with pepsin, which cleaved the mutant procollagen within the protease-sensitive non-collagenous insertion, producing a truncated alpha 1(I). This protease sensitivity demonstrated the structural distortion to the helical structure caused by the insertion. In long-term culture with ascorbic acid, which stimulates the formation of a mature crosslinked collagen matrix, and in tissues, there was no evidence of the mutant chain, suggesting that during matrix formation the mutant chain was unable to stably incorporated into the matrix and was degraded proteolytically.

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A splice donor site mutation in HOXD13 underlies synpolydactyly with cortical bone thinning

Gene ◽

10.1016/j.gene.2013.09.040 ◽

2013 ◽

Vol 532 (2) ◽

pp. 297-301 ◽

Cited By ~ 2

Author(s):

Xiuyan Shi ◽

Chunyan Ji ◽

Lihua Cao ◽

Yuhong Wu ◽

Yuyang Shang ◽

...

Keyword(s):

Cortical Bone ◽

Donor Site ◽

Splice Donor Site ◽

Splice Donor ◽

Site Mutation ◽

Splice Donor Site Mutation

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Aberrant splicing caused by a MLH1 splice donor site mutation found in a young Japanese patient with Lynch syndrome

Familial Cancer ◽

10.1007/s10689-012-9547-1 ◽

2012 ◽

Vol 11 (4) ◽

pp. 559-564 ◽

Cited By ~ 3

Author(s):

Masanobu Takahashi ◽

Yoichi Furukawa ◽

Hideki Shimodaira ◽

Masato Sakayori ◽

Takuya Moriya ◽

...

Keyword(s):

Lynch Syndrome ◽

Japanese Patient ◽

Donor Site ◽

Splice Donor Site ◽

Splice Donor ◽

Site Mutation ◽

Aberrant Splicing ◽

Splice Donor Site Mutation

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α-Thalassaemia as a result of a novel splice donor site mutation of the α1 -globin gene

British Journal of Haematology ◽

10.1046/j.1365-2141.2000.02225.x ◽

2000 ◽

Vol 110 (3) ◽

pp. 694-698 ◽

Cited By ~ 17

Author(s):

C. L. Harteveld ◽

C. Beijer ◽

P. Van Delft ◽

R. Zanardini ◽

L. F. Bernini ◽

...

Keyword(s):

Globin Gene ◽

Donor Site ◽

Splice Donor Site ◽

Splice Donor ◽

Site Mutation ◽

Splice Donor Site Mutation

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Functional changes in troponin T by a splice donor site mutation that causes hypertrophic cardiomyopathy

AJP Cell Physiology ◽

10.1152/ajpcell.1999.277.2.c225 ◽

1999 ◽

Vol 277 (2) ◽

pp. C225-C232 ◽

Cited By ~ 55

Author(s):

Hiroyuki Nakaura ◽

Sachio Morimoto ◽

Fumi Yanaga ◽

Masashi Nakata ◽

Hirofumi Nishi ◽

...

Keyword(s):

Amino Acids ◽

Troponin T ◽

Donor Site ◽

Splice Donor Site ◽

Wild Type ◽

Splice Donor ◽

Site Mutation ◽

Dependent Protein Kinase ◽

Dependent Protein ◽

Splice Donor Site Mutation

A splice donor site mutation in intron 15 of the cardiac troponin T (TnT) gene has been shown to cause familial hypertrophic cardiomyopathy (HCM). In this study, two truncated human cardiac TnTs expected to be produced by this mutation were expressed in Escherichia coli and partially (50–55%) exchanged into rabbit permeabilized cardiac muscle fibers. The fibers into which a short truncated TnT, which lacked the COOH-terminal 21 amino acids because of the replacement of 28 amino acids with 7 novel residues, had been exchanged generated a Ca2+-activated maximum force that was slightly, but statistically significantly, lower than that generated by fibers into which wild-type TnT had been exchanged when troponin I (TnI) was phosphorylated by cAMP-dependent protein kinase. A long truncated TnT simply lacking the COOH-terminal 14 amino acids had no significant effect on the maximum force-generating capability in the fibers with either phosphorylated or dephosphorylated TnI. Both these two truncated TnTs conferred a lower cooperativity and a higher Ca2+ sensitivity on the Ca2+-activated force generation than did wild-type TnT, independent of the phosphorylation of TnI by cAMP-dependent protein kinase. The results demonstrate that the splice donor site mutation in the cardiac TnT gene impairs the regulatory function of the TnT molecule, leading to an increase in the Ca2+ sensitivity, and a decrease in the cooperativity, of cardiac muscle contraction, which might be involved in the pathogenesis of HCM.

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