El derecho a la tutela jurisdiccional efectiva

As mentioned in Section 1.3.1, the KE family was first reported in the scientific literature by Hurst et al. (1990). The affected members of the KE family were described in that report as suffering from a "severe form of developmental verbal apraxia". Six representative case histories and a summary of the findings for four affected family members were provided. Articulation was reported to be defective; simple movements of the tongue and lips were unimpaired, but sequences of movements were impaired. The affected family members reduced consonant clusters, simplified sound structures, and reduced multisyllabic words to monosyllables or bisyllabic words. The histories of 16 family members revealed no feeding problems during infancy or any other neonatal complications. Hearing and intelligence were reported to be in the normal range, and there were no abnormal neurological signs (i.e. motor deficits) in the Hmbs. H urst et al. (1990) summarised the main impairment of the affected family members as "organising and co­ ordinating the high-speed movements necessary to produce intelligible speech".

Subsequent reports by Gopnik and colleagues (Gopnik, 1990a; Gopnik & Crago, 1991) suggested that the affected members of the family suffered from a specific deficit in grammar. These reports focussed on the linguistic deficits of the affected family members rather than the nonlinguistic deficits, previously described by Hurst et al. (1990) and elaborated later by Vargha Khadem et al. (1995). Gopnik's more recent views (Gopnik & Goad, 1997) describe a reformulation of this theory. They suggest a deficit in implicit rule-leaming forces the affected family members to leam verb forms as explicit lexical items. The suggestion that the utterances in which features were added result from the application of explicit rules was based on overt signs, namely hesitations or specific mention of the rule (such as "add an -ed") by the affected individuals. Gopnik & Crago (1991) also observed that word endings were sometimes added that did not obey the phonological constraints of the language. For example, when producing the plural of the nonword "sas", instead of adding -es, they lengthened the final / s /, conversely, they would erroneously add -es to words requiring -s, such as "zoop".

Fee (1995) addressed the possibility that the affected members of the KE family fail to produce correct grammatical inflections because of a phonological deficit. She reported that affected family members had difficulties with consonants and clusters at the ends of syllables. Seven of the eight members tested showed

devoicing (e.g. / d / pronounced as / 1/) and consonant deletion, and all eight showed cluster reduction. All such errors occurred at the end of a eitiier a syllable or a word. It should also be noted that the data of two affected family members were excluded because they were unintelligible. These data could be interpreted as problematic for the linguistic account specifying a deficit in grammatical morphology, because the phonological deficits are so severe as to impede detection and analysis of morphemes, particularly when these occur at the ends of words. Fee, however, interpreted these findings as supporting the linguistic account proposed by Gopnik and colleagues. Rather than reflecting a deficit in morphosyntactic rules, she suggested an impairment in constructing learned, language-specific, phonological rules.

Vargha Khadem et al. (1995) reported wide-ranging deficits in the KE family, revealing the impairments of the affected members on virtually every test of language administered. In addition, they reported on nonlinguistic deficits in oral praxis and nonverbal cognition. Their report was consistent with that of Hurst et al. (1990) but provided a fuller description of the behavioural phenotype in this family. The claim of a specific deficit in one aspect of language, such as grammatical morphology, seemed unrealistic in view of the range of impairments seen on other tests of language, and on nonlinguistic tests. The causal nature of these deficits, however, remains to be determined.

The orofacial praxic deficits shown by affected family members were examined in detail by Alcock (1995). She found that the affected family members were impaired m the production of sets of parallel or sequential nonspeech oral movements, as were patients with aphasia acquired following left hemisphere injury. In addition, the affected family members had difficulty with linguistic intonation, but they were unimpaired in the production of emotional intonation. Production and perception of oral and manual rhythm were also impaired in the affected family members, and they had difficulty articulating words in recitations or songs.

2.1.2 Genetic studies

The initial reports by Hurst et al. (1990) and Pembrey (1992) state that the occurrence of the disorder in almost half of the KE family, affecting both sexes equally, suggests an autosomal dominant mode of transmission. In addition, the high concentration of a distinct disorder in one family suggests that it is unlikely that the genetic abnormality is polygenic or multifactorial.

Fisher et al. (1998) reported the results of a genome-wide search for linkage in the KE family, identifying a region on chromosome 7 that co-segregated with the disorder. These results confirmed autosomal dominant inheritance with full penetrance. Further analyses of microsatellites from within the region enabled fine mapping of the responsible locus to a 5.6 centimorgan interval in 7q31. This locus was designated SPCHl. Statistically, this mapping was highly significant and there were no recombinants in this region. Thus, the data for each affected family member mapped successfully to this locus. These data indicate that the disorder segregating in the KE family is Hkely to have resulted from the disruption of a single gene. The alternative possibihty, however, that different components of the phenotype are the consequence of a contiguous microdeletion involving several genes in 7q31 caimot be ruled out.