Testis Biopsies Would Probably Yield Mutations For Autism

Someone could do testis biopsies and look for CNVs with the Affymetrix array technology in fathers with children who have autism and copy number variations that the parents somatic cells do not have. By the age of 34 men have accumulated germ line mutations that cause all kinds of genetic disorders. To add the assault of a barrage of innoculations to any inborn genetic variation that comes with increasing paternal age is key to increased non-familial autism, diabetes, schizophrenia, MS, cancers, lupus, obesity, fibromyalgia, Alzheimer's in the offspring of older fathers. If scientists do not want to publicize the paternal age effect in autism, cancers, diabetes, other autoimmune disorders they will not do this research.


1: Fertil Steril. 2007 Aug 11; [Epub ahead of print]
Increased achondroplasia mutation frequency with advanced age and evidence for G1138A mosaicism in human testis biopsies.
Dakouane Giudicelli M, Serazin V, Le Sciellour CR, Albert M, Selva J, Giudicelli Y.
Unité de Pathologie Cellulaire et Génétique, Université Versailles Saint-Quentin, Faculté de Médecine Paris-Ile-de-France-Ouest and Centre Hospitalier de Poissy-Saint Germain, Poissy, France.


1: Hum Genet. 2004 Aug;115(3):200-7. Epub 2004 Jul 7.
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Paternal origin of FGFR3 mutations in Muenke-type craniosynostosis.
Rannan-Eliya SV, Taylor IB, De Heer IM, Van Den Ouweland AM, Wall SA, Wilkie AO.
NDCLS, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe, Headington, Oxford, UK.
Muenke syndrome, also known as FGFR3-associated coronal synostosis, is defined molecularly by the presence of a heterozygous nucleotide transversion, c.749C>G, encoding the amino acid substitution Pro250Arg, in the fibroblast growth factor receptor type 3 gene (FGFR3). This frequently occurs as a new mutation, manifesting one of the highest documented rates for any transversion in the human genome. To understand the biology of this mutation, we have investigated its parental origin, and the ages of the parents, in 19 families with de novo c.749C>G mutations. All ten informative cases originated from the paternal allele (95% confidence interval 74-100% paternal); the average paternal age at birth overall was 34.7 years. An exclusive paternal origin of mutations, and increased paternal age, were previously described for a different mutation (c.1138G>A) of the FGFR3 gene causing achondroplasia, as well as for mutations of the related FGFR2 gene causing Apert, Crouzon and Pfeiffer syndromes. We conclude that similar biological processes are likely to shape the occurrence of this c.749C>G mutation as for other mutations of FGFR3 as well as FGFR2. Copyright 2004 Springer-Verlag
PMID: 15241680 [PubMed - indexed for MEDLINE]

From Wikipedia on Achondroplasia
However, in 3 out of 4 cases, people with achondroplasia are born to parents who don't have the condition. This is the result of a new mutation.
New gene mutations are associated with increasing paternal age (over 35 years). Studies have demonstrated that new gene mutations are exclusively inherited from the father and occur during spermatogenesis (as opposed to resulting from a gonadal mosaicism). More than 99% of achondroplasia is caused by two different mutations in the fibroblast growth factor receptor 3 (FGFR3). In about 98% of cases, a G to A point mutation at nucleotide 1138 of the FGFR3 gene causes a glycine to arginine substitution (Bellus et al 1995, Shiang et al 1994, Rousseau et al 1996). About 1% of cases are caused by a G to C point mutation at nucleotide 1138.
There are two other syndromes with a genetic basis similar to achondroplasia: hypochondroplasia and thanatophoric dysplasia. Both of these disorders are also caused by a genetic mutation in the FGFR3 gene