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The KE family is a medical name designated for a
British British may refer to: Peoples, culture, and language * British people The British people, or Britons, are the citizens of the United Kingdom of Great Britain and Northern Ireland The United Kingdom of Great Britain and Northern Ir ...
family, about half of whom exhibit a severe
speech disorder Speech disorders or speech impairments are a type of communication disorder A communication disorder is any disorder that affects an individual's ability to comprehend, detect, or apply language and speech to engage in discourse effectively with ...
called
developmental verbal dyspraxia Developmental verbal dyspraxia (DVD), also known as childhood apraxia of speech (CAS) and developmental apraxia of speech (DAS), is a condition in which children have problems saying sounds, syllables and words. This is not because of muscle weakne ...
. It is the first family with speech disorder to be investigated using genetic analyses, by which the speech impairment is discovered to be due to
genetic mutation Image:Darwin Hybrid Tulip Mutation 2014-05-01.jpg, A tulip flower exhibiting a partially yellow petal due to a mutation in its genes In biology, a mutation is an alteration in the base sequence, nucleotide sequence of the genome of an organism, ...
, and from which the gene
FOXP2 Forkhead box protein P2 (FOXP2) is a protein Proteins are large s and s that comprise one or more long chains of . Proteins perform a vast array of functions within organisms, including , , , providing and , and from one location to ano ...

FOXP2
, often dubbed the "language gene", was discovered. Their condition is also the first human speech and language disorder known to exhibit strict
Mendelian inheritance Mendelian inheritance is a type of biological Biology is the natural science Natural science is a branch of science Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific me ...

Mendelian inheritance
. Brought to medical attention from their school children in the late 1980s, the case of KE family was taken up at the
UCL Institute of Child Health The UCL Great Ormond Street Institute of Child Health (ICH) is an academic department of the UCL Faculty of Population Health Sciences, Faculty of Population Health Sciences of University College London (UCL) and is located in London, United King ...
in
London London is the capital Capital most commonly refers to: * Capital letter Letter case (or just case) is the distinction between the letters that are in larger uppercase or capitals (or more formally ''majuscule'') and smaller lowerc ...

London
in 1990. Initial report suggested that the family was affected by a
genetic disorder A genetic disorder is a health problem caused by one or more abnormalities in the genome In the fields of molecular biology Molecular biology is the branch of biology Biology is the natural science that studies life and li ...
. Canadian
linguist Linguistics is the scientific study of language A language is a structured system of communication Communication (from Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo ...
Myrna Gopnik Myrna Lee Gopnik (born 1935) is a Canadians, Canadian linguist. She is a Professor Emerita of Linguistics at McGill University. She is known for her research on the KE family, an English family with several members affected by specific language im ...
suggested that the disorder was characterized primarily by grammatical deficiency, supporting the controversial notion of a "grammar gene".
Geneticists A geneticist is a biologist who studies genetics, the science of genes, heredity, and variation of organism In biology, an organism (from Ancient Greek, Greek: ὀργανισμός, ''organismos'') is any individual contiguous system ...
at the
University of Oxford The University of Oxford is a collegiate university, collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the List of oldest universit ...
determined that the condition was indeed genetic, with complex physical and physiological effects, and in 1998, they identified the actual gene, eventually named
FOXP2 Forkhead box protein P2 (FOXP2) is a protein Proteins are large s and s that comprise one or more long chains of . Proteins perform a vast array of functions within organisms, including , , , providing and , and from one location to ano ...

FOXP2
. This discovery directly led to a broader knowledge on
human evolution Human evolution is the evolution Evolution is change in the heritable Heredity, also called inheritance or biological inheritance, is the passing on of Phenotypic trait, traits from parents to their offspring; either through asexual ...

human evolution
as the gene is directly implicated with the
origin of language The origin of language (spoken and signed, as well as language-related technological systems such as writing), its relationship with human evolution, and its consequences have been subjects of study for centuries. Scholars wishing to study the ...
. Two family members, a boy and a girl, were featured in the
National Geographic ''National Geographic'' (formerly the ''National Geographic Magazine'', sometimes branded as NAT GEO) is an American monthly magazine published by the National Geographic Society The National Geographic Society (NGS), headquartered in Was ...

National Geographic
documentary film A documentary film or documentary is a non-fictional film, motion-picture intended to "document reality, primarily for the purposes of instruction, education, or maintaining a Recorded history, historical record". Bill Nichols (film critic), Bi ...
''
Human Ape Human Ape is a National Geographic ''National Geographic'' (formerly the ''National Geographic Magazine'', sometimes branded as NAT GEO) is an American monthly magazine published by the National Geographic Society The National Geographic ...
''.


Medical investigations

KE family children attended Elizabeth Augur's special educational needs unit at
Brentford Brentford () is a suburban town in West London West London is the western part of London, England. The area lies north of the River Thames and extends from its historic and commercial core of Westminster and the West End of London, West En ...

Brentford
primary school in west London. Towards the end of 1980s seven children of the family attended there. Augur began to learn that the family had a speech disorder for three generations. Of the 30 members, about half suffer from severe deficiency, some are affected mildly, and few are unaffected. Their faces show rigidity at the lower half, and most cannot complete pronouncing a word. Many of them have severe stuttering and with limited vocabulary. In particular, they have difficulty with consonants, and omit them, such as "boon" for "spoon", "able" for "table", and "bu" for "blue". Linguistic deficiency is also noted in written language both in reading and writing. They are characterized by lower nonverbal IQ. Augur convinced the family to undergo medical studies and approached geneticist Michael Baraitser, of the Institute of Child Health. With colleagues Marcus Prembey and Jane Hurst, they started taking blood samples for analyses in 1987. Their first report in 1990 shows that 16 family members were affected by severe abnormality, though their hearing was normal and some had normal intelligence, and that the condition was genetically inherited (
autosomal dominant In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the Phenotype, effect of a different variant of the same gene on Homologous chromosome, the other copy of the chromosome. The first ...

autosomal dominant
). Upon the news,
BBC The British Broadcasting Corporation (BBC) is a public service broadcaster, headquartered at Broadcasting House in Westminster, London. It is the world's oldest national broadcaster, and the largest broadcasting, broadcaster in the world by ...

BBC
was preparing a documentary of the case in the scientific serial ''Antenna''. By this time, a Canadian linguist from
McGill University McGill University is a public In public relations Public relations (PR) is the practice of managing and disseminating information from an individual or an organization An organization, or organisation (English in the Commonw ...
,
Myrna Gopnik Myrna Lee Gopnik (born 1935) is a Canadians, Canadian linguist. She is a Professor Emerita of Linguistics at McGill University. She is known for her research on the KE family, an English family with several members affected by specific language im ...
, was visiting her son in Oxford, and delivered an invited lecture at the university, where she noticed the flyer for the BBC programme. She contacted the medical geneticists, interviewed KE family members, and returned to
Montreal, Quebec Montreal ( ; officially Montréal, ) is the List of the largest municipalities in Canada by population, second-most populous city in Canada and List of towns in Quebec, most populous city in the Provinces and territories of Canada, Canadian pro ...
. She was convinced that the genetic defect was largely centred on grammatical ability, and wrote letters to ''Nature'' in 1990. Her reports promulgated a notion of "grammar gene" and a controversial concept of grammar-specific disorder.


Discovery of ''FOXP2'' gene

Neuroscientist and language expert at the Institute of Child Health
Faraneh Vargha-Khadem Faraneh Vargha-Khadem (born 1949) is a British cognitive neuroscientist Cognitive neuroscience is the scientific field that is concerned with the study of the Biology, biological processes and aspects that underlie cognition, with a specific f ...
began to investigate teaming up with University of Oxford and
University of Reading The University of Reading is a public university #REDIRECT Public university #REDIRECT Public university #REDIRECT Public university#REDIRECT Public university A public university or public college is a university or college that is in state ...
linguists. In 1995 they found, contrary to Gopnik's hypothesis, from comparison of 13 affected and 8 normal individuals that the genetic disorder was a complex impairment of not only linguistic ability, but also intellectual and anatomical features, thereby disproving the "grammar gene" notion. Using
positron emission tomography Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in Metabolism, metabolic processes, and in other physiological activities including blo ...
(PET) and
magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging Medical imaging is the technique and process of imaging Imaging is the representation or reproduction of an object's form; especially a visual representation (i.e., the formation of a ...
(MRI), they found that some brain regions were underactive (compared to baseline levels) in the KE family members and that some were overactive, when compared to normal people. The underactive regions included
motor neurons A motor neuron (or motoneuron or efferent neuron) is a neuron A neuron or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapse In the nervous system In biology ...

motor neurons
that control face and mouth regions. The areas that were overactive includes
Broca's area Broca's area, or the Broca area (, also , ), is a region in the frontal lobe of the dominant hemisphere Hemisphere may refer to: * A half of a sphere As half of the Earth * A hemispheres of Earth, hemisphere of Earth ** Northern Hemisphere ** So ...
, the speech centre. With Oxford geneticists
Simon Fisher Simon may refer to: People * Simon (given name) Simon is a common name, from Hebrew language, Hebrew שִׁמְעוֹן ''Simeon, Šimʻôn'', meaning "listen" or "hearing". It is also a classical Greek name, deriving from an adjective meaning ...
and
Anthony Monaco Anthony P. Monaco (born October 10, 1959) is an American geneticist and university administrator. He has been president of Tufts University Tufts University is a Private university, private research university on the border of Medford, Massac ...
, they identified the exact location of the gene on the long arm of
chromosome 7 Chromosome 7 is one of the 23 pairs of chromosome A chromosome is a long DNA molecule with part or all of the genome, genetic material of an organism. Most eukaryotic chromosomes include packaging proteins called histones which, aided by C ...
(7q31) in 1998. The chromosomal region (
locus Locus (plural loci) is Latin for "place". It may refer to: Entertainment * Locus (comics), a Marvel Comics mutant villainess, a member of the Mutant Liberation Front * Locus (magazine), ''Locus'' (magazine), science fiction and fantasy magazine ...
) was named ''SPCH1'' (for speech-and-language-disorder-1), and it contains 70 genes. Using the known gene location of speech disorder from a boy, designated CS, of unrelated family, they discovered in 2001 that the main gene responsible for speech impairment in both KE family and CS was ''FOXP2'', and that this gene plays a major role in the origin and development of language. Mutations in the genes result in speech and language problems.


See also

*
Apraxia of speech Apraxia of speech (AOS) is an acquired oral motor speech disorder affecting an individual's ability to translate conscious speech plans into motor plans, which results in limited and difficult speech ability. By the definition of apraxia Apraxia ...
*
Developmental coordination disorder Developmental coordination disorder (DCD), also known as developmental motor coordination disorder, developmental dyspraxia or simply dyspraxia, is a neurodevelopmental disorder characterized by impaired Motor planning, coordination of physical m ...
*
Evolutionary linguistics Evolutionary linguistics or Darwinian linguistics is a sociobiology, sociobiological approach to the study of language. Evolutionary linguists consider linguistics as a subfield of evolutionary biology and evolutionary psychology. The approach i ...


References

{{reflist, 2 British families Evolution of language Speech and language pathology de:KE family