Tag: 上海水磨会所NX

Stuttering mice may help unravel mystery of human speech disorderStuttering mice may help unravel mystery of human speech disorder

first_img Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Sign up for our daily newsletter Get more great content like this delivered right to you! Country Mice supposedly don’t speak, so they can’t stutter. But by tinkering with a gene that appears to be involved in human speech, researchers have created transgenic mice whose pups produce altered vocalizations in a way that is similar to stuttering in humans. The mice could make a good model for understanding stuttering; they could also shed more light on how mutations in the gene, called Gnptab, cause the speech disorder.Stuttering is one of the most common speech disorders in the world, affecting nearly one out of 100 adults in the United States. But the cause of the stammering, fragmented speech patterns remains unclear. Several years ago, researchers discovered that stutterers often have mutations in a gene called Gnptab. Like a dispatcher directing garbage trucks, Gnptab encodes a protein that helps to direct enzymes into the lysosome—a compartment in animal cells that breaks down waste and recycles old cellular machinery. Mutations to other genes in this system are known to lead to the buildup of cellular waste products and often result in debilitating diseases, such as Tay-Sachs. How mutations in Gnptab causes stuttered speech remains a mystery, however.To get to the bottom of things, neuroscientist Terra Barnes and her team at Washington University in St. Louis in Missouri produced mice with mutation in the Gnptab gene and studied whether it affected the ultrasonic vocalizations that newly born mouse pups emit when separated from their mothers. Determining whether a mouse is stuttering is no easy task; as Barnes points out, it can even be difficult to tell whether people are stuttering if they’re speaking a foreign language. So the team designed a computer program that listens for stuttering vocalization patterns independent of language. The program listens to the number of vocalizations per minute and the length of pauses during bouts of vocalization. In humans, it can distinguish a person who stutters from a control subject 79% of the time. Emailcenter_img Click to view the privacy policy. Required fields are indicated by an asterisk (*) The program showed that mice with mutant copies of the Gnptab gene had less frequent vocalizations and more long pauses than normal mice. However, the afflicted mice produced all of the same sounds in the same proportion as their wild-type siblings, indicating they were still physically capable of normal vocalizations. And an array of cognitive and physical challenges showed that the stuttering mice were otherwise healthy. That suggests that despite the vast differences in complexity between human and mouse vocalizations, mutated copies of Gnptab have similar effects, the researchers write today in Current Biology, which makes the mouse a potentially valuable model for studying stuttering. “We can throw every drug in the book at it,” Barnes says. “We can try to figure out which part of the brain is affected.”“I think it’s further support that the genes in this pathway do have something to do with speech,” says Stuart Kornfeld, a cell biologist at the Washington University School of Medicine in St. Louis, who was not involved in the study.But how a single mutation in a common cellular housekeeping gene can result in stuttered speech remains unknown. One possibility is that the neurons involved in speech are particularly sensitive to the waste accumulation caused by missing lysosomal enzymes, Kornfeld says. But there’s no evidence for this yet, he adds; in fact, scientists don’t exactly know which neurons are involved in speech.The buildup of undigested waste products from a malfunctioning lysosome system is just one possible cause, says Tim Holy at the Washington University School of Medicine in St. Louis, Missouri, one of the paper’s co-authors. “Another possibility is that these genes have another function that has not yet been recorded in any other context.”last_img read more