Alzheimer and Parkinson diseases, frontotemporal lobar degeneration and amyotrophic lateral sclerosis overlapping neuropathology start in the first two decades of life in pollution exposed urbanites and brain ultrafine particulate matter and industrial nanoparticles, including Fe, Ti, Al, V, Ni, Hg, Co, Cu, Zn, Ag, Pt, Ce, La, Pr and W are key players. Metropolitan Mexico City health crisis is in progress.

The neuropathological hallmarks of Alzheimer's disease (AD), Parkinson's disease (PD), frontotemporal lobar degeneration (FTLD), and amyotrophic lateral sclerosis (ALS) are present in urban children exposed to fine particulate matter (PM2.5), combustion and friction ultrafine PM (UFPM), and industrial nanoparticles (NPs). Metropolitan Mexico City (MMC) forensic autopsies strongly suggest that anthropogenic UFPM and industrial NPs reach the brain through the nasal/olfactory, lung, gastrointestinal tract, skin, and placental barriers. Diesel-heavy unregulated vehicles are a key UFPM source for 21.8 million MMC residents. We found that hyperphosphorylated tau, beta amyloid1-42, α-synuclein, and TAR DNA-binding protein-43 were associated with NPs in 186 forensic autopsies (mean age 27.45 ± 11.89 years). The neurovascular unit is an early NPs anatomical target, and the first two decades of life are critical: 100% of 57 children aged 14.8 ± 5.2 years had AD pathology; 25 (43.9%) AD+TDP-43; 11 (19.3%) AD + PD + TDP-43; and 2 (3.56%) AD +PD. Fe, Ti, Hg, Ni, Co, Cu, Zn, Cd, Al, Mg, Ag, Ce, La, Pr, W, Ca, Cl, K, Si, S, Na, and C NPs are seen in frontal and temporal lobes, olfactory bulb, caudate, substantia nigra, locus coeruleus, medulla, cerebellum, and/or motor cortical and spinal regions. Endothelial, neuronal, and glial damages are extensive, with NPs in mitochondria, rough endoplasmic reticulum, the Golgi apparatus, and lysosomes. Autophagy, cell and nuclear membrane damage, disruption of nuclear pores and heterochromatin, and cell death are present. Metals associated with abrasion and deterioration of automobile catalysts and electronic waste and rare earth elements, i.e., lanthanum, cerium, and praseodymium, are entering young brains. Exposure to environmental UFPM and industrial NPs in the first two decades of life are prime candidates for initiating the early stages of fatal neurodegenerative diseases. MMC children and young adults-surrogates for children in polluted areas around the world-exhibit early AD, PD, FTLD, and ALS neuropathological hallmarks forecasting serious health, social, economic, academic, and judicial societal detrimental impact. Neurodegeneration prevention should be a public health priority as the problem of human exposure to particle pollution is solvable. We are knowledgeable of the main emission sources and the technological options to control them. What are we waiting for?

Further delineation of the clinical spectrum of KAT6B disorders and allelic series of pathogenic variants.

PURPOSE: Genitopatellar syndrome and Say-Barber-Biesecker-Young-Simpson syndrome are caused by variants in the KAT6B gene and are part of a broad clinical spectrum called KAT6B disorders, whose variable expressivity is increasingly being recognized. METHODS: We herein present the phenotypes of 32 previously unreported individuals with a molecularly confirmed diagnosis of a KAT6B disorder, report 24 new pathogenic KAT6B variants, and review phenotypic information available on all published individuals with this condition. We also suggest a classification of clinical subtypes within the KAT6B disorder spectrum. RESULTS: We demonstrate that cerebral anomalies, optic nerve hypoplasia, neurobehavioral difficulties, and distal limb anomalies other than long thumbs and great toes, such as polydactyly, are more frequently observed than initially reported. Intestinal malrotation and its serious consequences can be present in affected individuals. Additionally, we identified four children with Pierre Robin sequence, four individuals who had increased nuchal translucency/cystic hygroma prenatally, and two fetuses with severe renal anomalies leading to renal failure. We also report an individual in which a pathogenic variant was inherited from a mildly affected parent. CONCLUSION: Our work provides a comprehensive review and expansion of the genotypic and phenotypic spectrum of KAT6B disorders that will assist clinicians in the assessment, counseling, and management of affected individuals.

A recurrent de novo mutation in ATP1A3 gene in a Mexican patient with alternating hemiplegia of childhood detected by massively parallel sequencing / Mutación de novo recurrente en el gen ATP1A3 en una paciente mexicana con hemiplejia alternante de la infancia detectada por secuenciación masiva en paralelo

Abstract Background: Pediatric movement disorders represent a diagnostic challenge for pediatricians and pediatric neurologists due to their high clinical heterogeneity and shared common features. Therefore, specific diagnoses require different approaches including metabolic work-up and specific tests for frequent genetic conditions. Alternating hemiplegia of childhood (AHC) is an ultra-rare pediatric movement disorder, characterized by paroxysmal alternating hemiplegia, dystonia, and seizure-like episodes that can be misleading during the evaluation of a child with a movement disorder. Case report: We present a Mexican patient with abnormal movements referred to the Genetics clinic because of hyperammonemia and a possible organic acidemia. Our assessment did not find clinical features compatible with an inborn error of metabolism. A massively parallel sequencing approach with targeted panel sequencing was used to get a final diagnosis. A missense variant c.2839G>A (p.Gly947Arg) located at exon 21 of ATP1A3 gene was demonstrated. This variant (rs398122887) has been previously reported as de novo producing alternating hemiplegia of childhood (AHC). Conclusions: AHC is an ultra-rare syndrome presented as a movement disorder with seizure-like episodes and a unique facial phenotype. Clinicians should be aware of this combination in order to diagnose this condition in a timely manner. Massive parallel sequencing panels are emerging as the best approach to diagnose rare movement disorders and simultaneously rule out metabolic disorders and common epileptic syndromes.

Resumen Introducción: Los trastornos pediátricos del movimiento representan un reto diagnóstico para pediatras y neurólogos pediatras debido a su gran heterogeneidad clínica y características comunes compartidas. Por lo tanto, los diagnósticos específicos requieren de diferentes abordajes que incluyen la búsqueda de desórdenes metabólicos y pruebas específicas para condiciones genéticas frecuentes. La hemiplejia alternante de la infancia (AHC) es un trastorno pediátrico del movimiento poco común, caracterizado por cuadros paroxísticos de hemiplejia alternante, distonía y episodios semejantes a crisis epilépticas, que pueden resultar desorientadores durante el abordaje diagnóstico de un infante con un desorden del movimiento. Caso clínico: Presentamos una paciente mexicana con movimientos anormales referida a la Clínica de Genética por hiperamonemia y una posible acidemia orgánica. Nuestro abordaje no identificó características clínicas compatibles con un error innato del metabolismo. Se utilizó un abordaje basado en secuenciación masiva en paralelo para obtener un diagnóstico final. Se demostró una variante de sentido equivocado c.2839G>A (p.Gly947Arg) localizada en el exón 21 del gen ATP1A3. Esta variante (rs398122887) ha sido previamente reportada como de novo, ocasionando AHC. Conclusiones: La AHC es un síndrome excepcionalmente raro que se presenta con un trastorno del movimiento con cuadros semejantes a crisis epilépticas y un fenotipo facial particular. Los médicos deben ser conscientes de esta combinación con el fin de diagnosticar oportunamente esta condición. Los paneles de secuenciación masiva están emergiendo como el mejor abordaje para diagnosticar trastornos del movimiento raros y, simultáneamente, descartar trastornos metabólicos y síndromes epilépticos comunes.

A recurrent de novo mutation in ATP1A3 gene in a Mexican patient with alternating hemiplegia of childhood detected by massively parallel sequencing.

Background: Pediatric movement disorders represent a diagnostic challenge for pediatricians and pediatric neurologists due to their high clinical heterogeneity and shared common features. Therefore, specific diagnoses require different approaches including metabolic work-up and specific tests for frequent genetic conditions. Alternating hemiplegia of childhood (AHC) is an ultra-rare pediatric movement disorder, characterized by paroxysmal alternating hemiplegia, dystonia, and seizure-like episodes that can be misleading during the evaluation of a child with a movement disorder. Case report: We present a Mexican patient with abnormal movements referred to the Genetics clinic because of hyperammonemia and a possible organic acidemia. Our assessment did not find clinical features compatible with an inborn error of metabolism. A massively parallel sequencing approach with targeted panel sequencing was used to get a final diagnosis. A missense variant c.2839G>A (p.Gly947Arg) located at exon 21 of ATP1A3 gene was demonstrated. This variant (rs398122887) has been previously reported as de novo producing alternating hemiplegia of childhood (AHC). Conclusions: AHC is an ultra-rare syndrome presented as a movement disorder with seizure-like episodes and a unique facial phenotype. Clinicians should be aware of this combination in order to diagnose this condition in a timely manner. Massive parallel sequencing panels are emerging as the best approach to diagnose rare movement disorders and simultaneously rule out metabolic disorders and common epileptic syndromes.

Introducción: Los trastornos pediátricos del movimiento representan un reto diagnóstico para pediatras y neurólogos pediatras debido a su gran heterogeneidad clínica y características comunes compartidas. Por lo tanto, los diagnósticos específicos requieren de diferentes abordajes que incluyen la búsqueda de desórdenes metabólicos y pruebas específicas para condiciones genéticas frecuentes. La hemiplejia alternante de la infancia (AHC) es un trastorno pediátrico del movimiento poco común, caracterizado por cuadros paroxísticos de hemiplejia alternante, distonía y episodios semejantes a crisis epilépticas, que pueden resultar desorientadores durante el abordaje diagnóstico de un infante con un desorden del movimiento. Caso clínico: Presentamos una paciente mexicana con movimientos anormales referida a la Clínica de Genética por hiperamonemia y una posible acidemia orgánica. Nuestro abordaje no identificó características clínicas compatibles con un error innato del metabolismo. Se utilizó un abordaje basado en secuenciación masiva en paralelo para obtener un diagnóstico final. Se demostró una variante de sentido equivocado c.2839G>A (p.Gly947Arg) localizada en el exón 21 del gen ATP1A3. Esta variante (rs398122887) ha sido previamente reportada como de novo, ocasionando AHC. Conclusiones: La AHC es un síndrome excepcionalmente raro que se presenta con un trastorno del movimiento con cuadros semejantes a crisis epilépticas y un fenotipo facial particular. Los médicos deben ser conscientes de esta combinación con el fin de diagnosticar oportunamente esta condición. Los paneles de secuenciación masiva están emergiendo como el mejor abordaje para diagnosticar trastornos del movimiento raros y, simultáneamente, descartar trastornos metabólicos y síndromes epilépticos comunes.

Interactive and additive influences of Gender, BMI and Apolipoprotein 4 on cognition in children chronically exposed to high concentrations of PM2.5 and ozone. APOE 4 females are at highest risk in Mexico City.

Children's air pollution exposures are associated with systemic and brain inflammation and the early hallmarks of Alzheimer's disease (AD). The Apolipoprotein E (APOE) 4 allele is the most prevalent genetic risk for AD, with higher risk for women. We assessed whether gender, BMI, APOE and metabolic variables in healthy children with high exposures to ozone and fine particulate matter (PM2.5) influence cognition. The Wechsler Intelligence Scale for Children (WISC-R) was administered to 105 Mexico City children (12.32±5.4 years, 69 APOE 3/3 and 36 APOE 3/4). APOE 4v 3 children showed decrements on attention and short-term memory subscales, and below-average scores in Verbal, Performance and Full Scale IQ. APOE 4 females had higher BMI and females with normal BMI between 75-94% percentiles had the highest deficits in Total IQ, Performance IQ, Digit Span, Picture Arrangement, Block Design and Object Assembly. Fasting glucose was significantly higher in APOE 4 children p=0.006, while Gender was the main variable accounting for the difference in insulin, HOMA-IR and leptin (p<.05). Gender, BMI and APOE influence children's cognitive responses to air pollution and glucose is likely a key player. APOE 4 heterozygous females with >75% to <94% BMI percentiles are at the highest risk of severe cognitive deficits (1.5-2SD from average IQ). Young female results highlight the urgent need for gender-targeted health programmes to improve cognitive responses. Multidisciplinary intervention strategies could provide paths for prevention or amelioration of female air pollution targeted cognitive deficits and possible long-term AD progression.

Trisomy 1q41-qter and monosomy 3p26.3-pter in a family with a translocation (1;3): further delineation of the syndromes.

BACKGROUND: Trisomy 1q and monosomy 3p deriving from a t(1;3) is an infrequent event. The clinical characteristics of trisomy 1q41-qter have been described but there is not a delineation of the syndrome. The 3p25.3-pter monosomy syndrome (MIM 613792) characteristics include low birth weight, microcephaly, psychomotor and growth retardation and abnormal facies. CASE PRESENTATION: A 2 years 8 months Mexican mestizo male patient was evaluated due to a trisomy 1q and monosomy 3p derived from a familial t(1;3)(q41;q26.3). Four female carriers of the balanced translocation and one relative that may have been similarly affected as the proband were identified. The implicated chromosomal regions were defined by microarray analysis, the patient had a trisomy 1q41-qter of 30.3 Mb in extension comprising about 240 protein coding genes and a monosomy 3p26.3-pter of 1.7 Mb including only the genes CNTN6 (MIM 607220) and CHL1 (MIM 607416), which have been implicated in dendrite development. Their contribution to the phenotype, regarding the definition of trisomy 1q41-qter and monosomy 3p26.3-pter syndromes are discussed. CONCLUSION: We propose that a trisomy 1q41-qter syndrome should be considered in particular when the following characteristics are present: postnatal growth delay, macrocephaly, wide fontanelle, triangular facies, frontal bossing, thick eye brows, down slanting palpebral fissures, hypertelorism, flat nasal bridge, hypoplasic nostrils, long filtrum, high palate, microretrognathia, ear abnormalities, neural abnormalities (in particular ventricular dilatation), psychomotor developmental delay and mental retardation. Our patient showed most of these clinical characteristics with exception of macrocephaly, possibly due to a compensatory effect by haploinsufficiency of the two genes lost from 3p. The identification of carriers has important implications for genetic counseling as the risk of a new born with either a der(3) or der(1) resulting from an adjacent-1 segregation is of 25% for each of them, as the products of adjacent-2 or 3:1 segregations are not expected to be viable.

Perfil clínico de una cohorte de pacientes con síndrome de Silver-Russell atendidos en el Hospital Infantil de México Federico Gómez de 1998 a 2012 / Clinical profile of a cohort of Silver-Russell syndrome patients followed at the Hospital Infantil de México Federico Gómez from 1998 to 2012

Introducción: El síndrome de Silver-Russell presenta restricción del crecimiento intrauterino y posnatal, macrocefalia relativa y asimetría, entre otras características. Es causado por mecanismos genéticos y epigenéticos en el cromosoma 11p15.5 en el 40% de los casos y por disomía uniparental materna del cromosoma 7 en el 10%. Métodos: Se identificaron los pacientes con diagnóstico de síndrome de Silver-Russell del Hospital Infantil de México Federico Gómez atendidos de 1998 a 2012; se reevaluaron 20 pacientes según los criterios clínicos internacionales, y se confirmó el diagnóstico en nueve sujetos. Resultados: Todos los pacientes presentaron restricción del crecimiento intrauterino y talla baja, ambos criterios diagnósticos mayores. La macrocefalia relativa estuvo presente en el 78% y la asimetría corporal solo en el 33%. Otras características, como la acidosis tubular renal, estuvieron presentes en más del 50%. Conclusiones: El diagnóstico del síndrome de Silver-Russell es complejo, por lo que contar con criterios clínicos adecuados es fundamental. Dado que la talla baja es la principal solicitud de atención médica en este síndrome, es relevante establecer diagnósticos diferenciales y valorar el crecimiento y desarrollo de todos los pacientes para identificar a aquellos en quienes la talla baja forma parte de una entidad sindrómica y que serían candidatos para realizar estudios moleculares. Este abordaje tendrá implicaciones para su manejo, pronóstico y asesoramiento genético.

Background: Patients with Silver-Russell syndrome suffer from severe intrauterine and postnatal growth retardation, relative macrocephaly and body asymmetry, among other characteristics. It is caused by several genetic and epigenetic mechanisms in 11p15.5 in 40% of the cases and maternal uniparental disomy of chromosome 7 in 10%. Methods: Twenty patients with a diagnosis of Silver-Russell syndrome who were seen at the HIMFG from 1998 to 2012, were evaluated according to international clinical criteria confirming the diagnosis in nine of the subjects. Results: All patients showed intrauterine and postnatal growth retardation and short stature, both considered as major criteria of Silver-Russell syndrome. Relative macrocephaly was present in 78% of the patients and asymmetry in 33%. Other characteristics such as renal tubular acidosis were present > 50% of the cases. Conclusions: The clinical diagnosis of Silver-Russell syndrome is complex. Short stature is the main reason for seeking medical attention and is helpful in the identification of a differential diagnosis. This situation underlines the importance of growth and development evaluation of all patients and particularly in those with short stature to identify those cases that may require molecular studies, with implications in management, prognosis and genetic counseling.

[Clinical profile of a cohort of Silver-Russell syndrome patients followed at the Hospital Infantil de México Federico Gómez from 1998 to 2012]. / Perfil clínico de una cohorte de pacientes con síndrome de Silver-Russell atendidos en el Hospital Infantil de México Federico Gómez de 1998 a 2012.

BACKGROUND: Patients with Silver-Russell syndrome suffer from severe intrauterine and postnatal growth retardation, relative macrocephaly and body asymmetry, among other characteristics. It is caused by several genetic and epigenetic mechanisms in 11p15.5 in 40% of the cases and maternal uniparental disomy of chromosome 7 in 10%. METHODS: Twenty patients with a diagnosis of Silver-Russell syndrome who were seen at the HIMFG from 1998 to 2012, were evaluated according to international clinical criteria confirming the diagnosis in nine of the subjects. RESULTS: All patients showed intrauterine and postnatal growth retardation and short stature, both considered as major criteria of Silver-Russell syndrome. Relative macrocephaly was present in 78% of the patients and asymmetry in 33%. Other characteristics such as renal tubular acidosis were present > 50% of the cases. CONCLUSIONS: The clinical diagnosis of Silver-Russell syndrome is complex. Short stature is the main reason for seeking medical attention and is helpful in the identification of a differential diagnosis. This situation underlines the importance of growth and development evaluation of all patients and particularly in those with short stature to identify those cases that may require molecular studies, with implications in management, prognosis and genetic counseling.